I don't think the remaining German scientists really thought a practical atomic bomb could be made.
The OSS bugged the German nuclear scientists and when they heard the radio report of Hiroshima, the reaction was one of astonishment.
And, slave labor for that type of work wasn't exactly reliable, if not overtly sabotaging. V-2 production was thankfully slowed due to the fatally heroic efforts of some of them.
And when Heisenberg read a newspaper about Hiroshima, he called all of the scientists together and explained to them where they went wrong and the correct way to build an atomic bomb. The German scientists were stunned since the "superior" Germans totally missed such a simple concept.
Very true, I've read many survivors accounts from the labor camps describing how they would sabotage what they were making. A few grains of sand sprinked into a shell fuze, bearing grease container, etc.
From the article:"Most of the planes delivered were sent back because vital parts were missing. The Luftwaffe accepted only 900 planes."