If there's any kind of catastrophe, people are going to want the resources inside these things. They're not going to destroy the bunkers, just their occupants. Yeah, gas would do the trick. I'd suggest starting with CS, just to send a message.

Then just cut the doors open and loot the supply hoards. Convenient that you can look these things up on the internet and save map pins to find them in case of need...

They could do like submarines and have air scrubbers. That'd keep them going for a while with no vents.

I don't think that any outcome they foresee will have any relation to what will actually happen.

Gas masks don't help with total lack of oxygen. All you have to do is send pure nitrogen down the ventilation shafts, even if they tanked O2, that's maybe 10 hours per tank per person - how many tanks do you think they got with their $55K "Villa de Armageddon"?

The funniest part would be watching these chucklefucks trying to operate cutting equipment

But then what would we shit down?