It is probably too late for Ver to join the crypto exchange market after the rise of Binance and several others. If the report is true Ver will use Bitcoin Cash as the base currency but why bother, Bitcoin was always going to win the battle against Bitcoin Cash.
He is not late at all. Roger Ver can potentially change the entire crypto exchange market if he does things right. Just because he would use Bcash it won't make the exchange will fail. Think like this: People use Doge for exchanges because its fast, and low fees. So if Roger does something that would convince people to use Bcash than anything, then there's nothing wrong with that. Right now what the market needs is a decentralized instantaneous exchange ,and if Roger Ver or anyone else for that matter develops such an exchange and does a great follow up on it, then we enter a new era of crypto.
You raise some interesting points but if memory serves me correct Ver was an investor in ShapeShift, now look at the state of it.
With his reputation and track record I doubt he would contribute anything positive as all he does seems to have undercurrents of his desire to either control Bitcoin, to take over it or destroy it.