Considering ROG single handedly cost 10 points with his pathetic tackle (he only needed to grab and slow the guy down a bit so the cover could get there yet couldn't even do that), and last minute brainfart. I think it's fair to say he cost the match.
If Hook had been on the bench, the Lions would have won for sure.
There was also a blatant red card early on for Burger ruled a yellow. I don't remember any particular whining about the referee to be honest, aside from that incident where it was justified. As Dullonien said, Munster apologists aside, it was genuinely acknowledged that ROG was awful in that match, an utter nightmare.