Nope...you're only allowed 3 hours at the Polynesian. If you really want to do it, I think you can pay for valet parking and stay there.
A couple other suggestions to minimize your car travel: go ahead and park at the TTC. When the tram drops you off (or if you walk it), there is a short walk to the Polynesian. If you don't want to do that, you could take the resort monorail just one stop to the Poly. The walk is very short though (maybe 5 minutes, if that). In either case, your car is already at the TTC and you're good for the day.