Darren Fletcher's youngsters finished their Group G campaign with a third straight victory, beating Birmingham City 6-0 at Carrington, with goals from Jacob Watson, Gabriel, Rafe McCormack, Jay McEvoy, James Bailey and Rooney.
It followed wins over Brighton & Hove Albion and Middlesbrough in the nationwide competition.
The last-eight tie is to be held at the West Bromwich Academy on Tuesday 10 February 2026.
The 13:00 GMT kick-off is set to be shown live on MUTV.
The Under-18s' final game of the year is on Saturday, starting at 11:00 GMT, with Everton providing the opposition at Carrington.