All that stuff about Lahabrea is why I wish the developers had taken a mulligan on him instead of committing so heavily to him being gone. Speaking of which, how many of the Ascians are actually left by now?
By my reckoning it's three, but I'm not entirely sure on that count.
Nabriales is the first to die on screen, with Emmerololth being revealed to have died during the disappearance of the Isle of Val once the Eureka storyline was underway. The latter, from what I've heard, resulted in a minor plot hole in that the dead Ascian made an appearance after the disappearance of the Isle of Val. This could be explained away by the position being refilled, but we've not seen them since and none of the other positions have been refilled (as far as we know).
Then there's Igeyorhm and Lahabrea, followed by Mitron and Loghrif off-screen on the First. Gaius is revealed to have killed two offscreen as well once he reappears in Stormblood, judging by his collection. Then we kill Emet-Selch and, finally, Elidibus.
This leaves Fandaniel, and any two of the following: Pashtarot, Altima, Halmarut, and Deudalaphon. My money is on Pashtarot and Altima being the survivors.