It seems like the guy who's on top will always get the stalling call.
I won a match once by pulling my opponent into my rubber guard. I couldn't get anywhere with it but I kept trying to zombie or pump him, pulled rescue dog a few times and basically continued trying to attack - but my opponent couldn't move or one of my attacks would have worked. They warned him once and the second time I was given an advantage. The third time, it was two points. Crappy way to win but an even a worse way to lose.