Great thread. To the OP, many pointed out the poor decision to dive with a compromised reg. I would like to pile on, but I would be a hypocrite. I've done it and might have done the same thing as you. If my octo was fine, then I would have assumed the problem was the primary second stage. I have had plenty of leaky mouth pieces. If the octo started going wet on me, I would gone back to the primary to see which was worse, then use whichever to do a slow ascent while purging in order to get some air.