Translation:He is a man who knows what he wants.
Because that only applies to the case where a subordinate clause comes before a main clause.
Here you have main clause + subordinate clause + subordinate clause, i.e. the main clause is first, not last.
It's not really a rule about "verb comma verb"; it's a rule about "verb is the second thing in a main clause" combined with the fact that a subordinate clause counts as one "thing".