I am just about to install my spacer now. On the passenger side gaskets, the top gasket (bottom between the spacer and the head was fine) the little holes did not allow the gasket to sit flush. I reamed it out a bit and it was much more uniform. The most likely affected cylinders would have been #1 and #5, so I am pretty sure that isn’t your issue, but leaks will be problematic.
You have already taken care of sparks and coils that would also be likely targets. Your injectors are also not that old.
The only thing remarkable about your data is that 2 of the 10 cylinders (9/10) do not have misfires. (7 out of 10 were misfiring on your pre-reset). The other thing noticeable is a bunch of electrical type faults that ordinarily I would accuse a bad battery of, but I don’t see them in the second list. I think I asked this before but didn’t see a reply: Are all those quiescent and other errors gone?
Since 9/10 are not having problems (in either error list), in theory, you should be able to move things around from there and see what follows what. The only thing to give me pause is you have more misfires after the reset than before, so your errors may continue to spread (or not). Only multiple resets and re-runs of the codes will give you a better indication.
If you are still getting the battery errors I would look closely at the battery and or wiring harness to see if there are any clues there.
The sheer volume of misfires is interesting. There may be values you can log with VCDS that may give you a better understanding of the issue. Also the fact that you spewed detritus out the exhaust is concerning since there is only 1 source for that: your cylinders. However I am not sure that would have led to injectors being fouled.
You also may want to get a camera down the spark plug holes to see what the cylinders look like and if they have anything to say (probably not, but worth a peak).
Ed