Lichess problem number 30420 is wrong

The given solution is Qxf7+ Rh7 Qxf6 but there is Qxc1+ and Re1#
So the best move is Qxe8 instead of Qxf6

yes something seems to have gone wrong in the creation of that puzzle (perhaps it was a stockfish glitch in an earlier version when this puzzle was created). Also it helps when you actually link to the puzzle

http://en.lichess.org/training/30420

Also puzzle 2359 is flawed:
lichess.org/training/2359

I attempted 1... Qh1+ 2. Ng1 Nxe3 (if 3. Qxe3 Bxe3 evaluates as -14.9). The actual solution is mate in 3, which I agree is better but -14.9 seems winning enough.

Also puzzle 20799 is flawed:
http://en.lichess.org/training/20799

I played 1. Rf5+ which the computer evaluates as +20. The actual solution is an immediate forced mate, but I'd like to imagine that with a +20 advantage I'd have decent winning chances.

@Toadofsky, while I agree that absolute winning positions shouldn't be frowned upon, I also feel that puzzles should stress the best paths which in those cases are mates.