He KNEW the instruments were overwhelmingly telling him they were off-course
heKNEWthere was high ground ahead
heKNEW they were in breach of SOP's
he KNEW his own life and the lives of the Pax and crew were at risk
he KNEW the Captain was following a wrongful course of conduct.
This sadly shows that noone is free from blame regarding experience gradients in the pointy end.
An accident that is in a few ways a bit similar to this is the Korean Cargo 8590 where the Capt buried a 747 into a field just outside London. The unfortunate FO didn't dare speak his mind, but the FE did, to no avail. This was blamed on the Korean culture, but it seems Westerners are not so outstanding at CRM as some would like to claim.
Really really sad.