Moisture is the enemy of plaster.

Foundations should never be backfilled with clay due to the moisture retention. 

The concentration of the moisture was low- much less towards ceiling and wetter towards the floor. 

Hello,I decided to remove this bathroom wall to prevent moisture build up in the shower.I have a few questions on the removal of the studs. 

What I got must be cleaned with a PH neutral cleaner and does not stand up well to lots of moisture.

My Concern is there is clear proof that the first floor ceiling had a 4 x6 ft repair as Seller claims is from AC Blower replacement causing issues.The last Home inspection cleared the Townhome had no moisture in a couple of places where previous inspector suggested wet spots because of poor job (ethernet cable from exterior to a bedroom) and HOA related issue.This townhome also has various sink rust related leaks and caulk based fixes. 

I am especially concerned about mold and rot risks from moisture getting trapped between the layers of siding, and having this damage the structure.My final question is whether it would be worthwhile, over the course of the summer, to re-side the house so that there is no layering involved.

Make sure all windows work properly, make sure all doors work properly, check for potential foundation issues and moisture issues with professionals not just the inspection guy.

@Colleen F.When you buy pressure-treated dimensional lumber in Arizona, although it might come out of the same mill (it doesn't, usually), it is typically not the same wood species and it is typically not kiln-dried to the same moisture level as it is in Little Rhody.The wood species that deal best with the higher levels of dryness are more resistant to the pressure-treatment process compared with others.

Sounds like the pets have urinated enough to penetrate the the grout in the tile floor.