After spending a lot of time and energy to get a cat (Pippen, AKA big and stupid) out of our house when we were moving, I understand completely how this can happen. Pippen found his way under the floorboards, and was determined not to leave. It took my Dad and Father in law two weeks to coax him out of where he was and get him out of the house. They finally had to resort to a havahart trap baited with fish.