Put the males in one outside run, the females in the inside run and the children in the run between

And make sure the runs are covered.
I was going to buy the "accident" theory but how would 2 fires start accidentally and pretty much simultaneously in different areas of the cathedral?
Summary?
I think you should pour used motor oil on the stupid contractor. Then you can see if it really kills pests
I'm sure any slimy coating would kill some types of pests. I don't expect used motor oil would work better than a good coating of cooking oil.