Errr, Alonzo Church solved it first, Turing followed .. and both of their independent methods were heavily based upon similar earlier work by Kurt Gödel, with Church also incorporating ideas from Stephen Kleene.
There is no doubt that Turing was bright, very bright indeed, but next you'll be claiming he cracked the Enigmna Code or something.
There is a reason Turing is considered one of the greatest minds to ever live. He didn’t just invent a concept. He invented a completely new branch of science. We would’ve gotten there eventually but his idea to solve the Entscheidungsproblem using his machine was such a step ahead of the times that we christened him the father of an entire science.