What's clearing? I have never heard of that in reference to how a horse walks. That back left foot will land about 4" in front of the front. That's how he's always walked.
I , too, am a bit confused regarding the talk of "tracking up". Tracking up means that the hind foot reaches forward at least to where the front foot was placed. Over reaching means it tracks further than where the fore was. I think in the walk it is pretty normal to reach a bit beyond the print made by the fore, but in the trot, the rear should reach just TO the front, no farther. Because if it reaches farther, then it will strike the front foot.
I don't know why some folks are talking about overreaching and tracking up. I wanted clarification from them.
I am not seeing lameness in your horse either. I watched the video twice and I did not see lameness. His movement might be a bit unsteady under rider, and he did hollow out and dash forward in the "trot" under saddle portion of the video, but this could be just being green, new to a rider and/or a saddle that doesn't fit his unmuscled back.
I may be missing something, I admit to not having near as much experience as many of the members here. But I do not see lameness.
As regards the other matters, I have no real comment. I didnt' read the other threads. I think maybe you should have gelded him sooner, but you wiill have to wait. I do hope you don't end up with a foal that is an accident. It's kind of like the many puppies and kittens that are 'accidently' made. There are so many of them out there, and folks would rather buy a purebred. but , if you are certain it would be YOURs forever, then that is your choice.