[ET(end tyranny)]

Maybe he heard or saw a car or pedestrian outside and was waiting until he felt sure the coast was clear.

OR, perhaps waiting for a car to arrive to pick him and Elizabeth up?

[GovernmentShrinker]

Perhaps. The possibility of more than one abductor is something we haven't explored yet on FR (amazing to think that there's still an angle we haven't even speculated on, given the massive amount of speculation we've been doing).

I think it's sort of unlikely though, as it would be an awfully risky plan for the abductor who was in the house. But then again, being in the house in the first place was mighty risky, so your theory certainly can't be ruled out.