Axis Annie - S3-E23
Factual error: After Carter realises Hogan got the envelope off so fast, Newkirk says "Speedy Gonzales." 'Hogan's Heroes' was supposed to take place from 1942 to the end of the war. Speedy Gonzales first appeared in "Cat Tails for Two" in 1953.
Answer: It's a comedy, not a documentary.
stiiggy
Perhaps it was counterfeit. There are numerous episodes where they deal in counterfeit monies.