I feel like he is NOT unique, but I can't find much solid reference on him to confirm that 100%. The cardback is the distinct picture of him I can find and it appears to be a Hasbro creation. Most of the shots I could find from the cartoon had a bunch of the more generic super commando design, or the female super commandos (which I hope we also get in figure form someday). I never could actually find the captain design in the cartoon. (I think someone mentioned that he might show up in the sewers behind Maul at one point. This guy is definitely not supposed to be Gar Saxon either (who I also want).
I do really like the design though, and we never see his face. So for my purposes I am going to pretend he is more of a generic commander and just get a few of him.