I fought ogres twice in the same tournament ([TOW] Tournament Report - #2 by Vacationist)
My opponent wasn’t the best tactically, but I can say that our lovely multiple wound d6 war machines are quite the blessing against ogres.
High armor save was also surprisingly clutch.
Mournfang are glass cannons but hit like trucks, pepper them with magic missiles and preferably a dreadquake to slow their advance.