Mine is a 2018 Classic with two nuts and no cotter pin and with little 12mm nuts on the end of the swing arm. I think I now understand how it's all done and I thought I had all the right tools but my problem is how do you fit a socket onto each of the two nuts that hold the axle in place without damaging the exhaust. Is there some special technique? Are there any torque values I should be using?
It's tough because I can't see what you're seeing (+ I don't have a UCE), but I would say that if you can't fit a socket and socket handle in there then you have to use an open end.
I found that on my AVL I can remove (and retighten) the axle nut without having to put a wrench on the head of the bolt. But every bike is different. (Wow. What an understatement!).
As far as torque goes I don't know a number, but I have a pretty good feel for "nice and tight". I step on it with one foot, but not my full weight.