OP: does your husband have a cell phone, ipad, or laptop with him? If so, I suggest you download the Kindle app, and go to bookbub.com. It's a free subscription and catalog of ebooks in all formats. Prices are free-to-$2.99.
Sign up for wifi for the rest of the cruise, and download some books to read in quarantine.
I agree your husband should go with you to the quarantine hotel, since he's been exposed, but tested negative. He might have a problem with other hotels.