Yeah, there will be a clear reaction that the remaining bugbear besides Buga suddenly gets knocked out as well in the update. Anyways we do not go by turn order in the initiative (the only important turn order is when foes get to go and who goes before them). As everyone besides Mephis goes after bugbears, so once bugbears had acted then everyone can post in whichever order and I as GM handle it when actions are resolved and how (example cases if attack kills someone who other party member aimed to hit I move party member attack someone else example).