What software have you used for blending the two subframes into a single one? If you haven’t that greenish colourcast in either subframe - and you shouldn’t- the resulting frame should be clean.Unfortunately no, they don't. Have you actually used this DPRSplit app? On a couple of occasions I was able to recover some highlights.
But in general it doesn't really work as expected, merged files have no additional DR and it often creates an awful greenish colour cast in the highlights.
Good to have as a last resort, but I never rely on it. And I wouldn't recommend anybody to rely on it.
On another note, it has been proven and confirmed that there is about 0.7 to 1 full stop of DR improvement that we gain In the end.
Now, I am keen to understand what DR advantage a quad pixel RAW technology may provide in terms of Dynamic Range broadening.