Do you have a prior knee injury you have not told us about??
If not then you are not going to fucking hurt your knees unless you do something retarded. The minimal amount of knee wiggle in these videos is not of any significance. All your worrying is doing is dampening your fucking progress to becoming a man.
This guy has some serious knee movement and is still squatting almost double the weight without to much trouble. http://www.youtube.com/watch?v=rNpGTTR37mM
This does not mean you should go whilly nilly and squat without care, keep focusing on shoving those knees out every time you squat and use every warm up as time to drill the knees out. But you should still be adding weight every workout and you do not need to continuously ask our permission to add more weight. Watch your own videos and based on the feedback you have gotten decide whether it is acceptable to you or not.
Jesus Christ on a pogo stick.
oh yeah and the Chucks would be fine if you were doing a sumo stance powerlifting squat.. BUT YOUR NOT, so BUY SOME FUCKING SHOES!!!