I leveled a lot of characters in Vanilla and I remember Stitches being hostile on my earlier characters and neutral on later ones. I think a lot of players complained about being killed on the road by him and he got nerfed at some point. Of course that’s just how I remember it. It is totally possible that my brain decided to revise that memory.
If he’s despawning without a fight though, then that is definitely weird. I’m not in the beta to see it for myself though. Has anyone captured it on a stream?