Well techincally the refrigirator could have saved him. There was a small scene just so we could see the "made out of lead" sign. In theory lead is the most effective thing that can shield you from a nuclear blast and radioactive contamination. Sure that it was pretty far fetched but then again, what about Indianas miraculous saves from poisened darts, gun shots, arrows in the previous installments.
In general the whole Alien thing perfectly fits with everything that has been shown in the series. Aliens are no more stupid than the holy grail, lost arc of the jews or a Indian man pulling someones heart out while not taking the mans life at the same time. If we take this into account, we don't really have anything bad to say.
The only thing that made me somewhat mad was Mutt turning out to be Henry Jones 3rd. What a spectacular way to open up future sequals.
Personally i think that this part was quite good. The Indiana Jones series never treated itself too seriously and therefore i can't say that they overhauled with the idea or action seens (vine swinging included since it is possible to swing in such a manner, you just need to find a place with such vines). All in all a quite nice end to the series.
Deep into the darkness pearing
Long i stood there
Wondering
Fearing
Doubting.
