Is it conceivable that this sort of database error (if it is the problem) could occur on a RNP-AR/SAAAR approach where there is no way of checking the profile altitude/distance down the approach apart from perhaps total track miles to run (if it is displayed somewhere?).
I highly doubt it. There is a lot of double-checking going on with the FMS, GPS, eGPWS etc. behind the screen and
any discrepancy should trigger a warning in the scratchpad resulting in an evasive maneuver. Not sure if there is any protection against a corrupt database. There might have been recent changes I am unaware of, since I have changed equipment earlier this year.
The VNAV function seems a little buggy: One problem my company encountered with the E190 was with company RNV-F visual approaches into LGA runway 31 and DCA RNV-F 19. Half the time the VNAV would not capture. I heard from some check airmen that Honeywell tries to blame it on Embraer and vice-versa, in other words, the same blame game software companies play.
I learned quickly to not rely on VNAV on this aircraft.