Apparently I played the wrong mate in 1

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Harmbtn

https://www.chess.com/puzzles/problem/1485002

Alramech

Yep, looks like this puzzle has two valid answers.  When you come across these puzzles, I recommend reporting them: https://support.chess.com/article/1223-how-do-i-report-a-bad-puzzle

SHAYN6086F

by the way...

 

the rook is supposed to captuue

DeconanLeBarbaresque

Stockfish says that Rf8# is indeed the best move (even if that doesn't change the outcome).