Vaylen on the human side?

Hi folks! New convert to the BW system here with a quick question. Human figures of note on the side of the Vaylen are commonplace. But has anyone tried a Vaylen FON working for the humans?

Obviously, the circumstances would have to be bizarre. But if Vaylen come to see themselves as human, then might one come to some strange leap and turn against its species? Perhaps if it was in a host who was so emotionally broken the only strong emotion he felt was from fighting the Vaylen? Or, riffing off a line from Sheva’s War, if the last surviving Naiven from a clan wiped out during an invasion, with no offspring of his line to help become true Vaylen, threw in with humanity to get a measure of revenge on the Vaylen who sold out his clan to their doom?

My apologies if this has been asked and answered before!

I think this is an interesting idea. To clarify, though, I like to think of a ‘Vaylen FON’ as a figure of note whose actions assist the Vaylen cause, whether that character is Vaylen, human, or whatever; and whether or not the character knows the consequences of his or her actions.
So, the reverse seems possible: a Vaylen whose actions contribute to the human cause, making that character a ‘human’ FON. It certainly makes sense from the perspective of a Vaylen trying to become more human than human and ‘forgetting’ its identity or any number of other reasons. And it sets up some interesting scenes–what happens when the player characters discover that their biggest backer is possessed by the Vaylen? Or take it a step further–a Vaylen player character that doesn’t know she’s a Vaylen until halfway through the game…!
My point is that the ‘Vaylen as human FON’ should be a significant plot point in the game; if it isn’t, then the Vaylen might as well be a human. The Vaylen phase goals should be aimed at restoring the Vaylen nature to the FON–thus eliminating a ‘human’ FON, and causing the PCs to really look at their beliefs.