It will be She Wolf who takes him as her mate. That is why being a mate is more binding because it is the wolf who claims not the human. If that makes sense. Which can be fun to play with if a wolf chooses a mate and the human halves don't get along that well at first :)

I think we shouldn't make it spreadable, but if you are in a pack with two hybrids you do become slightly stronger and get some of the opposite abilities like we were talking about for the pack way back when. So at first they come to become hybrids but quickly learn they can't so they try to join the pack?