Hey man, nice squats, I like the advice you’ve been given so far, but I have a different take on things.
Also, stop watching so you think you can squat… I personally find that video awful and will do more harm than good.
What I like about your squat
knees forward - you’re sitting down instead of back, and that’s exactly what I would advise, and also the reason you got out of the hole with your max attempt. When you push your knees forward you get a lot more torgue on the knee extensors, putting them in a more optimal position to contract and gives more stretch reflex.
Below or at parallel - enough said
What I feel you can improve on
Low bar - this is the reason you’re bent over, the bar has to stay in line with your feet, so the lower it is on your back the more bentover you’ll be. I would highly advise you to go moderate bar, on top of the rear delts and below the traps. This will keep you more upright and you already have the quads to make it work. With the front squatting you’re already doing, you’ll get to 500 in no time.
Shoes - chucks or flats are decent, but what you really need are weightlifting shoes. These will help keep you more upright and allow you to bring more quads into the lift.
Hamstrings - yours are very tight, so tight you can’t even straighten your legs before your descent. This is also the reason for your minor pelvic rounding and likely back rounding. Just stretch them and do dynamic moves, don’t worry about them, they’re not as big a deal as people think, they don’t actually contract during the lift, what everyone forgets is that they’re a hip extensor AND a knee flexor, so they’re working against each other the entire lift putting them into an isometric contraction. Moral of the story, loosen them up.
What you can do to improve
chain squats - these are a great way to get thru your sticking point and emphasize the glutes which are primarily responsible for the lockout, 45-60 pounds of chain is ideal. Get a 3 foot feeder chain, and buy 3 foot lengths of regular chain, they should weigh about 7.5 lbs each, just buy the feeder chain and one set of chains to start, try it, then adjust from there.
Glute work - since the hamstrings aren’t actually doing much, you need to work your glutes like crazy, hyperextensions, glute bridges, kettlebell swings are all great, good mornings are also excellent, just bring awareness to the issue and that’s often enough.
Hope this helps you out man