So I set this up so that players get kits for diffrent ranks. for example when a player holds the lumberjack tittle they get a kit with 2 chainsaws and 200 LGF. The kit works and all while the tittle lumberjack is on the player... but once they lose the tittle the kit is still showing up and redeemable by the non tittle holder

After a second I see that its removing the BetterChat tittle but not actually removing people from the oxide group

Both titles and groups are updated in the same function (SwitchLeader)
It's a bit hard to test by myself but I don't see any reason why it wouldn't remove the group, and all groups are removed when the plugin is unloaded. 
Only thing I can think of is if the server was shutdown or crashed without the plugin unloading correctly could provide a means for the group removal/management to be bypassed

so wouldnt the next time the server restarted would the addon just fix the groups/permissions? Because at this current point theres players with access to kits they no longer hold the tittles for.