That's a very old school way of finishing the heel hook which seriously increases the risk of injury for your partner and decreases your control of the submission. I mentioned before that I've trained with the Renzo NY guys and they all heel hook, apply pressure, and no one gets injured because it's a slow, controlled, and very painful submission.
You can even see from the still on the video Jake looks like he's going to scream when Eddie demonstrates the proper pressure for a heel hook.
Rob Bernacki actually did a mini series on the Danaher heel hook recently but it keeps getting taken down whenever someone uploads it. He actually explains it much better than simply saying "toes to butt". Basically you want their toes in your armpit, but space between the rest of their foot and your torso. Draw your hooking thumb to your chin and your chin to your thumb and that puts a strong toe hold pressure on the foot. You can add a bridge to destroy the knee, but that's the part that shouldn't be done in training.