Attitude
From where suddenly come the ideas that the attitude indicators were giving false indications? Wouldn't such a thing, massively important, have been reported in the BEA note?
The "failures" that are distilled from the ACARS messages have been explained a long time ago: systems report OWN failures, but also failures FROM OTHER SYSTEMS, with whom they communicate. Because of that setup, you may encounter the system identifiers IR1, IR2 and IR3 in situations where,e.g. the Air Data units are faulty.