Well, RE6 sold around 800 thousand copies in its first month in North America. And by the end of Capcom's 2013 fiscal year five months later, it had sold 4.9 million copies, down from a projected 7 million.
RE7 will absolutely pay for the failures of RE6, at least initially. The change from action back to slower-paced survival horror might hinder its chances as well. But word of mouth will likely allow the game to be a pretty big success long term. But I doubt it will hit 6 million+ sales in its lifetime, which would put it at around RE6's numbers. And that's fine, because the game has very likely been budgeted with realistic sales goals in mind. I think it's pretty safe to assume the return on investment for this title will be stronger than it was for 6 and maybe even 5.
They way I see it,Capcom is willing to take a short term hit in order to establish longterm legs by making a solid game.
Hope it pays off.