Revealing mistake: In a hallway scene, where the transformed Martin Brundle is throwing one of the scientists upstairs towards a guard, you can see the wires the scientist is hanging on. (01:23:05)
Revealing mistake: When Beth is helping Martin out of Bartok's cocoon, you can see Martin wearing pants inside the cocoon. Surely he should be naked. (01:35:15)
Revealing mistake: In the scene where Martin Brundle has transformed into the fly he kills one of the guards by breaking his neck. After this he throws the body towards a door where another guard is standing - the body is a plastic dummy as it flies across the room with no effort at all and when the other guard behind the door checks the body you can see a plastic yellow face which is supposed to be the guard that was killed.
Chosen answer: Presumably they go on to live relatively normal lives. The scene at the end of Bartok is meant to show that his employees have no sympathy for any creature, including him, who is suffering. At least some of them are aware it's Bartok, yet they allow him to be imprisoned and gawked at, just as they did the dog.