---Chase broke his skull, he walked out of a rehabilitation hospital---

Because of prayers?

Prayer is sitting quietly and talking to yourself.

This might have some results on your subsequent actions but can not influence any other person.

Or because of medical science?

Because of the skills that doctors have learned, despite the church's objections over many centuries, where what caused the cure.

Miracles are by definition impossible because they require the suspension of the laws of nature which, if that occurred, the universe would self-destruct.