Yes, VERIFYING is a Scrabble word!

Letter values in Scrabble US: V 4, E 1, R 1, I 1, F 4, Y 4, I 1, N 1, G 2.

Is it a valid word?

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

confirm the truth of
check or regulate (a scientific experiment) by conducting a parallel experiment or comparing with another standard
attach or append a legal verification to (a pleading or petition)
to declare or affirm solemnly and formally as true

Not playable in Scrabble US: CONFIRMATIVE, VALIDATORY, VERIFICATORY.