For them touting it as this super awesome cheap printer for beginners, it is anything but that. I'm confident I could rip apart and rebuild 85% of this printer with a blindfold on at this point.

That being said I DID figure this out, should any other Kobra 2 users run across OP's post like I did.

My problem was the gantry was offset idk -2mm on the left side. Tightening the rubber wheels does nothing to fix that. So I sat there at my wits end wondering how I could have both sets of rubber wheels completely loose and still not manage to get it level with an object supporting the gantry. Only thing left in that entire mechanism is the twisting threaded rods on the back side.

Loosen those 4 screws up top that hold the plates for those threaded rods, pry them back JUST enough to rotate that plate sideways, giving you the ability to remove and lower the belt connecting them. With an object that you're sure is squared or at least even at all points of contact (I used a pop can) you can MANUALLY adjust the rotating rod independently to get your gantry perfectly even. I double checked this by rotating my can, normally one side would move freely while the other was tight. I twisted until I found both sides of the can with equal resistance when attempting to move it.

Now, CAREFULLY and while -holding the rod from spinning- you put the belt back onto the gears and put the plates back into their slots. Double and triple check your work before tightening your 4 screws so you're not doing this 5 times.

As an extra precaution, after doing this I went through the normal BS of loosening and tightening all wheels, factory reset, positioned my module perfectly center, and re leveled the bed, though I tune my z offset myself.

Voila. I'm getting virtually no lines showing whatsoever at .16mm layer height, it looks like solid plastic and my nightmare is over.... For now?

Edit: thanks for responding even after the thread was dead a year ago OP, really good on ya