Well,....the unfortunate part is that they are probably permanently "sealed in" as you said, and unless they are removed, they will likely die in there.
I would STRONGLY suggest that you put a couple water bowls down in a couple out of the way places in there, so they don't die from lack of water. Healthy snakes can go many months with no food,....but without water, they will die in fairly short order.
There HAS to be someone,(friends of other friends, etc..) teenage sons of your friends, etc..
In any case, please do the water bowl thing as I mentioned,...this will allow you a TON of extra time to deal with finding someone. The very LAST thing you want, is for them to die from lack of water inside the building, and then stink up the place because of their dead carcases,....not to mention having to rip the place apart to even find where the stink is coming from. Then of course, the smell will be "infused" into everything inside......yes, the waterbowl is the smartest thing you could possibly do in this situation. It will allow you PLENTY of extra time you otherwise wouldn't have.
best regards, ~Doug
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"Better to be silent and thought a fool, than to open mouth and remove any doubt!"