Oh god, that will frustrate him to hell and back, though I half expect he will fortunately be cautious in applying his magic to begin with, because he does know thankfully somewhat from experience that magic does tend to operate differently on different worlds.

But not being capable of doing what he knows he's fully capable of back home or on the ship will be extremely frustrating, especially if someone he cares about is hurt and he can't just magic the injury away for them as he normally could. It should be a lot of fun to explore. He'll no doubt try to knit the wound at least once, but he'll cease the attempt once he realizes that's doing so is doing more harm than it is good.