Yes, EXODUSES is a Scrabble word!

Letter values in Scrabble US: E 1, X 8, O 1, D 2, U 1, S 1, E 1, S 1.

Is it a valid word?

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

a journey by a large group to escape from a hostile environment
the second book of the Old Testament: tells of the departure of the Israelites out of slavery in Egypt led by Moses; God gave them the Ten Commandments and the rest of Mosaic law on Mount Sinai during the Exodus

Also: book of exodus.