My advice: choose lighter openers next time. Something you can do for a triple. Going heavy on openers will make you more tired for the following attempts, and those are the ones you want to count towards your total.
Here’s what I saw.
I don’t agree that your opener was the problem in this case. If you watch the 485 squat again carefully you will notice that in the hole your torso is hitting your thighs, jamming you up. As a result you don’t hit depth and your back rounds out failing in the bottom position. Strengthwise I see you capable of 500 or perhaps a little more.
Bring your feet out and open up your hips, mobility allowing. How much you open will be the result of experimentation. When you hit the sweet spot, your body will lock in at the appropriate depth. Once that’s dialed in you only need to think of force.
You could use some more torso bracing. I can’t tell if its weakness or lack of bracing technique from the video, you’ll need to figure that out. One thing that worked fro me during cycles is overloads. After my last squat of the day I would add 50 lbs, walk the weight out and hold for 10-15 sec. Next I would add 50 more lbs and simply stand and hold weight without walking out. Careful to brace HARD the entire time.
Finally good mornings wouldn’t hurt
I’d like to add wearing socks with a bomb on them ok for gym. Probably not the best for a meet ha ha
But yea lower the openers more and build the total I see too many people open then get nowhere because they are expecting to pr on the second and bigger pr on the third. I go for 5 lbs better then my best gym lift on third if IF I’m feeling great