Yes, MISCUE is a Scrabble word!

Letter values in Scrabble US: M 3, I 1, S 1, C 3, U 1, E 1.

Is it a valid word?

MISCUE is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a faulty shot in billiards; the cue tip slips off the cue ball
a minor inadvertent mistake usually observed in speech or writing or in small accidents or memory lapses etc.

Also: slip-up.

Not playable in Scrabble US: PARAPRAXIS.