People don't actually think they'd kill of Y'shtola just like that, do they?
Because even if they were to kill off XIV's cross-series representative, why in Heavens would they spoil that outright in a trailer?!

She's obviously wounded though, probably just an excuse to take her out of the story for a time and give focus to others. Seems like it might happen during the initial incursion into Gyr Albania, so pretty early into the MSQ? Think she'll recover later in 4.0, or sometime later on in 4.X?