RJ has confirmed those women were not survivors from the AOL. These AS joined the Jenn Aiel in the decades surrounding the founding of the White Tower. The scene were they appear ancient is set several centuries later. The harsh environment they lived in for centuries likely made them age faster (and look older) than average, and not all AS live 600-700 years. Some in the Tower already have signs of great age, like grey hair at 150 (so likely 300 in the AOL. People who live nearly as old as Cadsuane are the exception, not the norm. Don't forget that AS are killed (from having used the Binder), roughly in their middle years. It does not make them age twice as fast, it kills them suddenly in midlife. They never die from "natural causes" and thus they believe channelling makes them immune to all the ailments of old age, and immune to most diseases. That's not entirely true, as we know. Some of the Forsaken mention their fear of the nasty diseases they could catch in a primitive world like the Third Age's (and their doctor isn't exactly one they ever wish to have perform any cure on them!) - so it follows a channeler could eventually catch those and require healing to survive them, not to mention that channelers eventually experience decay like everybody else (eg: Cadsuane's ancient, and toothless, wilder) - it's just unknown among AS because they all die at half they lifespan. Channelling seems to boost the immune system to an extent, and the rest is due to the fact Aes Sedai die from the Binder before entering the phase of their life where they'd be far more likely to develop cancers, cardiac problems and a great deal of syndromes that are far more common past mid-life.

The Aes Sedai in Rhuidean were more likely born fairly late in the Breaking, I would say. The conditions no longer existed for AS to enjoy their AOL lifespan. The same would be true of AS, if not for the Binder. Healing would help, certainly, and they have better living condition than most, but people just don't have modern lifespans (though Jordan has pushed the boundaries of realism somewhat, having a little too many people living way past what is now considered mid-years but who would not so long ago been considered ancient, or exceptional. Mind you, perhaps it's a misconception - if we look at the Two Rivers sample, there seems to be Cenn Buie, then the next oldest characters shown - like Tam, Egwene's parents and so on are many decades younger. They're still a bit exceptional for 18th century conditions, though we have to account for the fact it's pre-industrialization).