Reverse Alcatraz mount escape

Seen the new MTS and saw this escape whilst at HQ but didn't get to drill it, the reverse Alcatraz mount escape. With this escape is the key to it the kneebump forward. So say I've hooked his foot with my right foot, is the key to bump him forward with my right knee and using the elevation from hooking his foot I bring my left knee in through the game, I've probably made it sound a lot more confusing than it is

Basically what I'm trying to say is the important part is knee bumping him forward? And the hands, what do they do? Drilled it tonight but I think we were hip bumping rather than knee bumping him forward

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