My wife used to work for a ServiceMaster franchise.  If insurance is paying for it let them and go do something fun.  They have access to some specialty "fire-chemcials" that do a great job, but they're kind of like restricted use pesticides.  If you aren't trained you are better off not messing with them.

Anything you do is going to interfere with their work.  Walk away and let the pro's do it.  That's why you carry insurance.  You are probably dealing with the crew from Effingham?  They seem to be a pretty good outfit