Either Jordan was being "devious" and the Raven tattoo was meant to represent her murder by the Shadow, but this is rather weak symbolism, as Min specified this wasn't just any kind of Raven but it looked like a picture of one, a tattoo - and that speaks clearly of the Seanchan, not the Shadow. A tattooed mark suggests ownership, or a deeper association, or a claiming of some kind. The Raven can be a symbol of the Shadow, but the Viewing would at least suggests she was BA, or would be turned etc. - not killed in a fight against the Shadow.

More likely, in the context of the Viewing and all (RJ was building up even then to the Seanchan vs. WT war), the Raven tattoo meant Carlinya would be owned by the Seanchan down the line, most likely as a damane (which would make her Property, she doesn't have to have been literally tattooed, damane aren't - the tattoo would symbolize she's owned), this is a continuity error. Carlinya was probably to be captured by the Seanchan during TG, the battle(s) that will lead Egwene and the Seanchan to make a deal of some kind during TG.

We'll never know for sure what happened. Perhaps RJ forgot the Viewing and Brandon simply followed his outline by killing Carlinya in the fight against Mesanna.

More likely IMO, Carlinya is a background character (there must be tons of those) RJ didn't mention at all by name in his notes and outlines for AMOL - Brandon would have needed to check in her character file to find a mention of the viewing or something of this kind - and Brandon thought he had complete freedom to do with her as he pleased, and when he decided (or followed RJ's notes) to include women of Sheriam's circle in the showdown with the BA and Mesaana, he thought Carlinya was one of those he could kill, oblivious to the fact there was a Viewing pointing in another direction.