I don't seem to be able to get credit for defeating General Kordax. I have beat him twice solo and I have the mission in my journal but it doesn't get completed when I beat him and I never got the feat either. This is on the USPS server on a PS5.
He's the one you have to hit the cog on after you beat him up, I think. Make sure you are doing that, and if you still don't get credit, let us know.
I guess it's not a bug. Since you don't have to arrest other bounties, I just missed the prompt to arrest him. I mean, it doesn't indicate that you have to arrest him afterwards in the journal entry and there is no indicator that there is something more after you defeat him, so I didn't realize I had to do that. My character was also using range attacks to defeat him so I wasn't close to him when he was defeated and didn't get the circle prompt (on PS). I guess if I was in melee range I would have seen the prompt. So while it isn't a bug, I do think that there should either be an overhead prompt or have it be part of the journal, where after you defeat General Kordax, it tells you to arrest him.
Yeah, this one has been an annoying issue for a long time. You are not the first to get hit with this, and I doubt you will be the last.