It looks like the tractor is broken in the middle.
BINGO! It's back is broken.
If you look closely, you can see the middle of the tractor moving up and down as the FEL is moved, which is especially evident when it reaches the end of it's travel. It's also noticeable when the operator very briefly lifts the front of the tractor with the FEL.
Less obvious but quite pronounced, if you know what to listen for, is the sound of the tractor as it is operated. Notice how it sounds "trashy" or "loose", as if gears are grinding or something is broken inside. If you compare the two video examples, the difference is very obvious.
Another huge red flag, is the fact that first video of the broken tractor starts with the tractor already running and the operator never increases the RPM's above idle and goes very slowly when driving it. The operator of the tractor in the second video starts the tractor, immediately revs the RPM's above idle so the hydraulics will operate properly, then drives and operates it in much the same way as anyone might do.