Your only going one way if it doesn’t feather, and that’s down!
Yes, both for lack of power to climb with the remaining power against an unfeathered prop, and the probable need to reduce power on the remaining engine to maintain straight flight. I opine that's what happened here, a skilled pilot, on top of his game, with a good second crew member, assessed well, and did only what was needed to get the plane safely back on a runway. They made excellent, non rushed, intelligible radio calls, and flew exactly where they needed to be. A better outcome would hardly have been possible!