May try the following :
this disableAI "AUTOTARGET";
this allowFleeing 0;
Or maybe you should setcaptive the enemies to TRUE until the group arrives to the desired location,then setcaptive them to FALSE again.
Use a trigger.
Act : EAST Present
RADIUS : value that'll cover all the enemies.
On Act : {_x setCaptive TRUE} foreach thislist;
Not sure if that will work because the enemies will still shoot the group....
Try it and if that doesn't work, Wait for further and possibly better replies from others.
Regards,
Haroon1992