Maybe you could take your bunny to the rescue, have them bond him with another bunny, and then take the two home, putting them in a new cage/fenced in area - an area where bunny #1 doesn't have his scent marked.....then let them move into the original space together, at home. Just a thought and maybe not a solid one at that. I just think the rescue folks know the personalities more than we do. Like I said, it took MONTHS for my two to like each other. They look like mutt and jeff. One is tiny and furry and one is huge and sleek furred. One is a Jamora bunny and the other is a meat rabbit. (ewwwwwwww.....how could anyone eat my Denver bunny?)