Everyone wears protective gear when they look for the money and when they exam the money at the bank. Nobody is wearing protective gear when they go to the hotel room to check out the dead man and Quincy picks up the half eaten apple. The Agent Frank Parker leading Quincy into the room stated that his people left everything the way it was.
However, the only thing they did before he got there was disinfect the room to render it safe to enter.
However, the only thing they did before he got there was disinfect the room to render it safe to enter.
Quincy's ruse to ask people to bring in their money because it's counterfeit wouldn't have worked. People know that counterfeit money can't be redeemed and people wouldn't willingly surrender their money. This ploy has actually been used successfully by real life law enforcement.
When Quincy and Sam drive off from the scene, in the sheriff's car, the shadow of the camera and someone moving is on the passenger side.
At nearly halfway into the program, FBI Agent Haber mentions that the money taken by the hijacker was marked and the serial numbers were recorded, even though there was no way the government agencies which did so had prior knowledge that it would end up on a plane which would later be hijacked.