Re: ankle mobility help needed
Good videos. Bad squat.
You have a major motor control fault before we worry about mobility. If your have "Becoming a Supple Leopard" see page 82 for Air Squats.
You are driving your knees forward instead of sending your hamstrings back and down.
A great drill to fix this is go to Home Depot and get two scrap pieces of 2 x 6 about 2' long (will be near the saw where they cut wood for customers). Balance the boards vertically about 1" in front of your toes in your squat stance. Your mission is to learn to squat, while keeping tight back position, to full depth, without knocking over the boards.
I my guess is your ankles may not be great, but have enough range of motion to squat once you learn how to squat correctly.