Customer service lacking

Maybe look into the Lemon Laws of your state if you haven't already. I don't see any manufacturer paying you a refund for your lost mortgage payments, it simply doesn't happen as it would undoubtedly open a set of flood gates not to mention admitting wrong doing. The extended warranty probably not either unless it was their own plan (I don't know if Winnebago even has their own). It is unfortunate what you've gone through and I hope you get a resolution, but it's probably not going to be what your asking unless it's forced (ie: court). Good Luck.

EDIT: as I was typing this the above poster pretty much covered what I was saying. LOL
I was in the new car business for many years and dealt with these kind of complaints along with a few Lemon Law cases.