Just been reading about these with the thought that there's be some sort of limit the body can take to the shocks they give out, but it sounds like this was essentially a known possibility and it's sort of the whole point of them.
So as long as his condition hasn't actually gotten worse, he wouldn't need to stop playing, it's just be weather football clubs are happy to put up with the chance of him having it happen while playing, and clearly his clubs so far have been