I ended up making the changes to buddypress. I set registration.php to display profile group 3 instead of 1, to hide the required display name option on signup, which forces it to clone username data. I then removed the ability to change names in xprofiles’ edit.php. Those 2 steps take care of all future occurances, so I then went in and changed all of my users display names to match their usernames manually, via the dashboard.
Problem solved.
Works like a charm. Thank you very much!
