Actually, this might be one of the only plays Harry could have made which wouldn't have that result, because it seems the purpose of the trap is to lock away Voldemort's shade where it can't access other victims even by leaving his body. If Voldemort died while talking to Dumbledore, his shade would probably still be stuck inside the mirror world.

Although speculatively, this might not work because his shade has no reflection, but if that were the case then Voldemort would have an out even given the powers Dumbledore already knew him to have.