"Well if we expect the facility to be on high alert AFTER we collapse the roof, then the key is to cause the collapse from the outside thus eliminating the need for extraction.  If we can get some sort of explosive that can be detonated remotely, then all we need do is get at least one of us in, if the other can't get in we can leave them as backup.  Plant the explosives and then get out of their before we blow them.  Are there any remote explosives available to us for this?"