Here are Mcvay's comments about this today; .
TLDR: he acknowledges that as the rule is in the rule books, the ruling makes sense. He doesn't think the rule was intended to give a team two points after the conversion is "rejected". After the "rejection" the play should be over. He doesn't think ANYONE would disagree with him and he would feel that way even if it benefited his team. (Which I don't believe for a moment.) Since he is a member of the competition committee, he is sure this will be addressed in the offseason.
He was also upset by how long it took between the play and when they were notified that it was being looked at. I think he said it was about a minute and a half.
By his logic, if a team blocks an extra point kick, the play should be over, no runback possible by the blocking team. After all the extra point was rejected. His players had every opportunity to grab the ball and didn't.