Batteries for Class A

I am not sure why you even removed the batteries from your motorhome. I lived in Marietta for decades and the temperatures never go so low that battery removal is remotely necessary. Exercising your generator monthly, as required, will keep the batteries charged so that them freezing is not possible.

All of that is for the future, however. I would just replace the one damaged battery with a replacement that is as close to the original one as possible.