Yeah, the above advice is all really solid. North south is okay, but that puts pressure on your neck before you get there. Step 1 is to at least threaten Von flue to take off pressure on your neck. You are in position in the video, just smash your weight through your left shoulder into his neck. Step 2 is start posturing a little while keeping pressure on the Von Flue. Then, you can either go knee-on-belly, north south, mount, or finish the choke. Or, sit there for 90 seconds while the guy dies from your weight on his chest and neck ... he is pulling you down on top of himself.
Just be careful of the 2 main threats. First, he obviously would love to recover guard or hit his knees into a front headlock or guillotine. Easy to avoid, blocking his hip and keeping weight on him, just be aware. Second, he will try to use neck pressure to roll you over your head. Just be aware of your base, and be ready to sprawl harder or post your right hand out if necessary.
Just be careful of the 2 main threats. First, he obviously would love to recover guard or hit his knees into a front headlock or guillotine. Easy to avoid, blocking his hip and keeping weight on him, just be aware. Second, he will try to use neck pressure to roll you over your head. Just be aware of your base, and be ready to sprawl harder or post your right hand out if necessary.