BuddyPress.org

Fixed it! I had some mismatch going with my custom MU themes where the theme that was appearing wasn’t set to active by MU since i had a backup of my theme in the themes folder (with the same styles.css and same theme title… doh!)
Also one more caveat not mentioned in the bp-language process is that the overrides don’t seem to apply to existing activity but rather new activity. That makes for some interesting testing if you’re not aware of it.