I've managed, with a bit of research, to find the full statements made by President Emil Hacha's daughter Milada Rádlová at Nuremberg.
Hoggan has said regarding this:
Hacha’s daughter denied to Allied investigators, after World War II, that her father had been subjected to any unusual pressure during his visit to Berlin.
David Hoggan, The Forced War: When Peaceful Revision Failed (Institute for Historical Review, 1989), Pp. 248
Hogan's most recent footnote (74) after having written this sentence, takes us to page 634, where the footnote reads:
74. Trials of War Criminals, October 1946-April 194, vol 12, pp. 867-874
So I went about looking for this specific volume. I wondered whether or not, because Hoggan's footnotes sometime seem sparse, whether or not he just lumps in many sources, or one source into a single footnote after each section rather than continuously citing footnotes where relevant. I found this to be true, even though it makes the book harder to read, and harder to discern what sources he is using.
I managed to find volume 12 of the Trials of War Criminals relating to that section of the sub-chapter, and Indeed it does read exactly as Hoggan has written. However, by page 874 there was no mention at all of Hachas daughter. This to me, seemed like it was confirmed for sure that Hoggan just didn't cite a source for it. Which, is actually true. Hoggan didn't cite a source for this, because he was lying about it. At least, that's currently what it seems like.
I was about to give up looking for the testimony, when I decided to look up "Milada" in the same volume I had recently checked regarding the Hoggan volume. Surprisingly, I got a match. In this volume, on page 902, is the "Extracts from the testimony of the prosecution witness Milada Radlova".
Her selected testimony in this volume goes from pages 902-907.
Q. About what time, to the best of your memory, can you recall your father returning to the hotel?
A. Around 5 (/clock in the morning.
Q. Can you describe his physical condition as you then saw him, to the best of your recollection ? A. He was very tired, pale, and completely broken.
Q. You say completely broken?
A. Yes.
Q. Can you remember if your father said anything?
A. Yes. He came and said the situation was very bad ; that he was forced to sign a document * and that Dr. Chvalkovsky would read the document to us; that he had been put before a fait accompli by Hitler—that means the occupation of Bohemia and Moravia.
Q. Had he signed this document or was he going to sign this document later?
A. That had already been signed when he came back. When the document was read, my father drew our attention to two things. They were—that he had asked that his proclamation in that document would say that the fate of Bohemia and Moravia is in the hands of Hitler and not, as the Germans made the draft, that he puts the fate of Bohemia and Moravia into the hands of Hitler.
Q. You said there was a second point?
A. And the second point was that my father scratched out on the document the words "In the name of the Government" because he, as a lawyer, knew that according to our laws such a document would be invalid because the president may not sign any such treaties without the government.
Q. Thank you very much, Mrs. Radlova. Did your father do
anything further at that time?
A. He was very tired and retired.
Q. What time the next day did you leave for Prague from Berlin?
A. Eleven o'clock in the morning.
[...]
Q. I'm sorry. Mrs. Radlova, can you remember during this trip back, or at any subsequent time, anything that your father might have mentioned to you with respect to his conference with Hitler?
A. Yes. My father told me again, he repeated that Hitler had put before him a fait accompli; and that Hitler shouted at him and that he said it was an irrevocable decision to occupy Bohemia and Moravia ; that every resistance he would meet with would be broken with bloodshed. At the same time my father told me that Goering said that if my father would not sign that document, he would be forced immediately to make an air attack against Prague; and that—although without any pleasure—he would be forced to do that because Prague was a beautiful city but he would be forced to destroy it completely, so he could show the Western Powers that the German air force can show something.
Q. I see. Was any reference made to an agreement, that you can remember, or talk of an agreement that you had previously mentioned? I will repeat the question: During the course of your subsequent conversation did you ever refer to the agreement between Hitler and —
A. He only talked about the document he had been forced to sign.
Source:
https://archive.org/details/trialsofwarcrimi12inte/page/906/mode/2up?q=Milada+
I should say, that this is "selected" testimony, however what has been quoted even if selected doesn't vindicate what Hoggan claimed, in fact, it's just the opposite. It's compounded by the fact that Hoggan didn't cite the page numbers for this source, even though it would've been pertinent to do so considering he had literally cited this same volume in that section of his book. It seems like deception.
Even though this doesn't look good, we need to keep an open mind about this. I checked the origianl German edition of Hoggan's book too, just to see if perhaps there was a difference, unfortunately, this issue with the source is repeated:
Der Erzwungene Krieg, Chapter 10 "Der Hitler=Hacha=Pakt", Pp. 336, footnote 83, Pp. 819The reason I checked the German edition was because of the somewhat sordid history of the English edition of Hoggan's book which has been discussed elsewhere on the forum. So it was my though that perhaps this could've been one of the mishaps due to that controversy, but that doesn't seem to be the case. Although perhaps the original, never published English version of "The Forced War" contains footnotes not printed in any edition of the book that has been published since 1961. We probably won't ever know.
I will say this though, Hacha's daughter is lying. From the transcript:
Q. Can you tell this Tribunal, Mrs. Radlova, whether during the course of this lunch your father mentioned the possibility of a trip to any place?
A. Yes. I remember that my father came from his office, greeted our guest, and at the same time apologized that perhaps he might be forced to finish the lunch quickly; that perhaps he would be forced to go to Berlin, that Hitler desired that he leave for Berlin immediately by plane, that my father refused because he was old and sick and never had made a trip in a plane.
Q. I see. In other words, Mrs. Radlova, you have just informed this Tribunal that the suggestion for the trip to Berlin came from Adolf Hitler and not your father?
A. That is right.
Pp. 904
This is blatantly untrue. Many authors, AJP Taylor, Ian Kershaw, DC Watt, John Toland, Norman Stone, Christopher Thorne, Udo Walendy, and no doubt many others have all confirmed that it was in-fact Hacha who requested to meet Hitler in Berlin via the Czech foreign minister František Chvalkovský:
Instead Chvalkovský telephoned his message. President Hacha would like to come to Berlin to see Hitler. Hencke insisted on having this in writing. The request duly arrived, at 11:25 a.m. on March 14.
D.C. Watt, How War Came: The Immediate Origins of the Second World War, 1938-1939 (Pantheon Books, New York 1989) Pp. 152
Even though it looks like Hoggan lied about this, I'm hesitant to believe it's that simple. Just think about it, this isn't a very "good lie" as far as lies go, it's a pretty damn easy lie to get caught up on, and for that reason I find it suspicious, why on earth would you lie so badly? And through sources which can be so easily checked? Why lie at all? Why not just avoid saying more than you need to, in no other account that I have ever read regarding the Hacha trip to meet Hitler have I seen it written the comments by Hacha's daughter. Who's account, in reality, we cannot actually verify for sure. Her testimony doesn't become the de-facto truth, it just means that she did not claim what Hoggan claimed that she claimed.
Perhaps it's even possible that she denied it somewhere else after the tribunal, I do not know. Unless anyone else has any ideas or other sources to add, this case is pretty much closed regarding this statement. At least in my opinion. Anything could turn up.