あれ?お前ケガ治ってね?
It is at the end, and I don't really understand why. Why would a person choose to use te form? (btw the person saying this doesn't say anything after, so I don't think its some kind of connective)
This is a very casual, slangy form of 「治ってない(か)?」 (not sentence-end ね). It's a little hard to say without context, but it sounds like the wounds healing was a surprise to the speaker, and the ~ている form is used in this case because the wounds have healed, rather than it being a future event.