Copley giving up 5 when he should've given up 3 just means he's less awful than Quick and Cal, not that he's good. While you're right about the skaters needing to be in position for a rebound (on that play, Lizzo can't get turned outgoing to the net and Mikey is floating in front looking for his guy to pick up), that doesn't mean Copley can't redirect the puck. That shot wasn't moving so fast that he couldn't have redirected it while ignoring his 5-hole.
It's that kind of thing that prevents him from being a true starter level goalie, his processing is too slow alot of the time. He had time to rotate his stick towards the shot for a redirect, but couldn't. On Aho's near OT wraparound goal, he takes too long to get over and recognize that Aho's speed is taking him across the ice, and he probably should've scored the winner on that