Jay does a small double-take at the indicated stain - he'd noticed it but hadn't really registered it, what it meant, if only because Tim was walking fine.

"Wh- Holy shit," he blurts, fingers tensing in his pockets. "What do you mean he fixed it, what, like with magic?"

That isn't, absurdly, out of the realm of possibility here, and it would be the only way Tim could possibly be maneuvering as well as he is.

The bigger issue here is somebody stabbed Tim. Maybe self-defense, maybe on purpose. He starts walking a little faster, leading them out of the park and angling toward the apartments.