That is what bcash is right now. A captured blockchain. You transact on it at the sufferance of the chinese government. If you think they won't exert that power, if they think it suits their interests, I'm not sure understanding this will convince you.
https://cash.coin.dance/blocks/today
Doesn't look like any pool is dominating unless Bitmain controls many smaller pools.
However, I'd argue that any domination is a side effect of Bitmain being the 1000pound gorilla in BTC to start with. THeir BTC pool is at 20%. (there are a LOT of people unhappy with Bitmain's business practices).
I mean there is no cost effective hash/kw alternative to Bitmain S9s.
The scary thing is that my friends and colleagues are buying S9s because no real alternative exists if you want to mine BTC(and I suppose Bitcoin Cash too)