Absolutely valid and relevant question. I can't imagine any referee disallowing the goal and insisting they take the FK because he's "not allowed to play advantage on a RC" - which I think does call the decision to bring play back into question.Here is a hypothetical. What would the referee have done if the shot had gone in?
What would the comments here be? Great advantage right?
However it's an easy sell in this case, so you can't blame him for going for that, even though it did essentially give them two chances from a single foul.