This is driving me insane

I foolishly purchased a v3se on sale last year, it printed pretty well at first but at some point maybe 6 months ago maybe more it started z banding.

I have read 100s of pages and posts, I have watched at least 4 hours worth of videos, i have cleaned, greased, lubed, and even completely disassembled the extruder and the zrods, cleaned, releveled, and reinstalled everything. Every single adjustment has been touched. Nothing has fixed this z banding from hell for me.

I've tried calibrating esteps, turning off linear advance, I've bolted the top frame to the wall to prevent the shaking, I've tried every nozzle in the house, brand new filament, old filament, and yet after the 2 hours of work tearing it all down it still has the issue.

Pictured is one of the worse prints that shows it off. Some filaments and some files hide it well but any square object will have them to some varying degree. I don't think it's temps I've done pid.

The only thing I found is the printer uses plastic trapezoid z nuts instead of brass. I have no idea if these are delrin or Chinesium. The one for the master rod was a bit wobbly and the one on the slave rod was nice and precise. As far as I can tell you cannot purchase these z nuts as they're a different design than earlier ender 3s and are flat on top. I also found typically they aren't meant to be very tight on the rod anyway but that's the single physical problem I found. As far as I can tell the z rods are straight, though the top of them is secured by bearings and they hold the belt tension so I don't think I can unconstrain the tops.

Please help if you can any advice is helpful because I'm just about ready to put the thing through the wall.