Perfectly true, their reaction to the news of the Hiroshima
bomb was initially disbelief. They firmly believed they
were in the lead and since they 'knew' a bomb was years
away there was no way the western allies could have done this.

Farm Hall was a well the part of misinformation campaign of the victors.

First message they want convey was "German Scientist were unable to calculate
critical mass"
But they had a problem namely according Wehrmact documents a Wehrmact physicist
(Deibner)calculated critical mass exactly and reported it to Wehrmact in
Feb.42.
So apparently German scientists forgat in Farm Hall what they knew in Feb42!!.
So this misinformation campaign collapsed but another one launched to replace
it namely "Good German scientists (Heisenberg)sabotaged evil Nazis nuclear bomb
making plans"
This could be good starting point for a Hollywood movie but licht years away
from the reality.Heisenberg could not sabotage anything because he was wrong in
41 as he was in 45.
Only key person in German nuclear program who might have a reason to sabotage
program was Houtermans but his background was very well known,anything less
than success would mean sure death for Houtermans and probably for his family.

BTW according to pre Farm Hall planning,only two of Farm Hall Guests supposed
to leave Farm Hall as free man.,but none of them got jailed.
Food for thought.