The "merge" conclusion has been proposed so much because they already have a track record of it, both KR and ID were merged into the main branch after they stopped being as lucrative as Riku wanted. We honestly don't know how it will end, maybe Niji kills off the branch and graduates half of the members while the ones loyal to the corpo get integrated, maybe they shut it down completely and try again in a couple of years like what happened to Shanghai and Taipei which got canned and served as the basis of VirtualReal, nobody knows.
The only certainty is that loosing ground in EN is bad for Niji, all of their competitors are establishing footholds in the market and they have foolishly destroyed theirs, while their home market is still ten times larger it's never good when all of your business rivals are doing something and you aren't. Even if the EN market is rebellious, contrarian and may not be super profitable in the future (nobody can truly say for certain) the limited birthrates and decaying economy of japan mean that the home market won't be unshakeable forever, at least growth in other asian markets with growing buying power and populations like SEA is needed if westerners are too annoying to deal with, but surprise, surprise, Niji fumbled that one too.