Perhaps this would work best as a counter to the armbar escape, where the guy being armbarred spins under his own arm and comes up with his head outside of his opponents legs, then you slap on the Viking choke.
I think he was saying they are going for an oma, then back up to wrap the head. Otherwise Chris is correct. It is also the wrong arm for an arm bar attempt (for the side he is on). It is however possibly applicable for the leg over guard pass, but it would still be very risky, and prob low percentage. Just my $.02