He would get help from Looney, if he needs it. I'd be more concerned with Donald's quickness than his power. Donald is not big by DT standards. He's 6'1" and about 280 lbs. He uses his speed and quickness to beat blocking schemes. I said last week it would not surprise me if Connor Williams started over Su'a-Filo this week. Su'a-Filo is bigger and stronger than Williams but Williams is quicker. I expect him to struggle with Donald, but I can see Su'a-Filo getting beat all night by Donald.
The Cowboys should be ready to move the pocket. Williams is better on the move than standing still.