You know, this is actually a very weird one. There's some reference to it happening, such as here:
But there's just not a lot of real info on it or mention of it.
Now, it's possible they just bought OC&C Boston and Greater China as the below article suggests. Not positive as to whether it was a full acquisition or not.
But this seems to suggest EY wanted to buy them, but the courtship never really happened (the first link, crunchbase, is created off of an automated system so I wouldn;'t entirely trust it).
My verdict: I'm fairly confident it is its own company