Well this seems... hard. I might not have gotten the DET/50s square wrong if I hadn't guessed Pete Babando, who apparently left DET after the '49-50 season!
He and Tony Leswick are the only 2 players who have scored a Cup-winning Game 7 OT goal, and both were for DET within 4 years in the 50s ('50 + '54), so if I had just remembered which was which year and taken Leswick instead, that would have worked...
Other miss was Ratelle, who I forgot started with NYR, I thought it was the other way around and that he was on the '70 Cup winner for sure...