FMB Stuka Escort problem

[Racetrack]

Hi guys I'm just editing a mission in wich me and my friends have to divebomb some tankers over the PortSmouth Harbour. I've setted two flights of Bf with their waypoints targets setted on our waypoints. The problem is that when the enemies reach us our escort start to fight and leave us alone, so while our escort si fighting against some enemie's aircraft the rest of the enemies start follow us from there to the Obj doing a massacre... So how to let our escort to protec us better?