The comments on Wookieepedia grew out of massive discussions both here and on Obsidian's boards.
There are adamant positions on both sides, but no conclusive evidence to neither support nor deny the idea. So it comes down to a purely personal evaluation. I tend to think that Kreia is Kae for the very reasons mentioned here and because her "betrayal in the heart", which is a prerequisite for becoming Darth Traya, is tied either to Revan or Yusanis or both. After all, assuming Kreia is Kae, it would mean that Yusanis refused to join her when she embraced the dark side and abandoned her - she was rejected by the man she loved and the father of her child. And he was then killed by her own favorite apprentice, Revan. Lots of betrayal in Kae/Kreia's past that way.
Another reason is the similarity of names. It's like Kae is the LS incarnation, Traya the DS incarnation, and Kreia the balanced "greyish" person we seen throughout most of TSL. And the name Kreia can be seen to be a combination of the two extremes: Kreia = K(ae) + (T)raya = Kraya = Kreia (just spelled a bit different, but pronounced the same).
But conclusive evidence either way? No.