The difference in the two videos is about 100 lbs on the squats. In the one that you got the ok on you do 170 and are able to control the weight on the decent much better, at 265 you are not controling the weight and letting it push you down, and your knees foward, at the bottom. i had the same problem but was able to fix it by working on decent mechanics as recomended by Coach Rip. Perhaps the same approach may work for you?
-Robert