I believe Detroit has clinched, unless I missed something in my hand-checking. The tiebreaker is common opponents, Detroit is 4-1 and El Paso is 3-3, and your last game is a common opponent. If Detroit loses and El Passo wins, your common opponents will be 4-2 vs 4-3, so 4-2 is a better winning percentage than 4-3.

I'm not sure why the clinching logic didn't award it to Detroit but the elimination logic appears to have it correct.