Houses older than that often have DIY dishwasher installs that you may have to work on a little.I made sure the dishwasher drain hose went from the dishwasher, all the way up to the underside of the countertop, and then back down to the drain connection on the disposer under the sink.

Was heading in the direction of coating the 'underside' of the house with Kilz.

I also suggest looking in the attic at the underside of the roof decking for signs of water staining as well as newer looking sections of decking.

Maybe have your cleaners check the underside of that Jeep out too.

The trick is to notch the underside with a router or table saw.

Typically go from slab to under side of roof deck, a continuous fire proof layer like sheetrock or densglass on both sides of wall. 

I don't think the ozone machine will work totally until you eliminate the main source of the smell.On the kitchen smell, have you cleaned the underside of the range hood, and taken out the fan filter and ran it through the dishwasher?  

Replace with some nice ABS or PVC, tie it in with some hubless fittings, support the underside, then cover it up.

The fire rated wall must extend to the underside of the roof sheathing.I dont think there is a rated wall that only has fire rated drywall on one side, but there may be some novel assembly that was approved.In my area, to refit the firewall, I had to removal all drywall and replace with 5/8" fire rated drywall, which had to be inspected once it was installed, but not finished (no taping or mudding).

If you did and this was not contained in the report, then you have two possibilities:1) If it is something the building inspector should have caught (you will need your contractor / roofer) to provide you with a professional opinion, then it may be deemed an error/omission by your inspector (he has insurance for this);2) If it can be demonstrated that the seller intentionally camouflaged the defect such that the building inspector could not have been expected to discover the issue [remember the inspector is conducting a visual inspection and is not permitted to open walls, etc. ... though they are expected to enter the attic space and examine the underside of the roof], then you "may" have recourse to the seller.