Idk. If anyone else hard trouble with siege of the warmind on lvl 30 with that ogre but if anyone is there's one solid way to take him down easily without running. When the ogre shows up just just hide and wait for the knights to show up kill BOTH..,,BUT don't kill the acolytes that spawn. They will retreat and run away to cover without the knights around thus leaving your fire team to blow him up with no hassle. Its worked twice so far.