What I was thinking about going to full wolf form is that, except for the few people that work with the wolves every day and the most frequent visitors, everyone would either assume it's a different wolf, or assume that they didn't accurately remember how much of said limb said wolf was missing. Presumably those few people that would notice the changes would be associates of the Pack, so they could theoretically conceal the fact by referring to the werewolf by a different pet name and, if the sanctuary has a website, putting his old pet name in a memorial page. Then once the wolf's limb had healed completely, he could either keep living as a wolf in the sanctuary, or they could gather the pack to see if he's ready to join the rat race, and if so, how and when they're going to reintroduce him.
A wolf in a park might not have any tabs kept on him, but human beings have plenty, so chances are he'd have to get a new identity. That's another reason I think some werewolves might not make the transition back.