What happens is Dats gets the benefit of the doubt because he actually plays pucks with his skate like that on purpose. Like in this case, he receives the pass at his feet either before or at the blue line, and the refs who are so accustomed to him using his feet gave him "possession" even though he technically skates ahead of the puck across the line. He maintained possession and no one was checking him for the refs to say he didn't have it. If that had been Tootoo it would've probably been called offsides.
I think it's pretty safe to assume that if the puck is within 8' of Pavel, then he has control of it. Doesn't matter who has the puck.