who will not be playing green and why?

[Sinistria]

No, they hadn't but there is the possiblity.

But if green or blue is underpopulated in 3 years, what should they hinder.

Or at least maybe they are so kind and make a transfer since merge is not coming.

Whatever, 3 years is a long time and who knows what will be.
I think the chance of a lot of fun starting with a bunch of people naked in nek-forest is worth to try it.