1. Also might want to ask ck pool OP if he is merge mining Bitcoin Cash with your hashrate? Just wondering for a friend.
I am not defending anyone here, but this question is just wrong, it's technically not possible to merge mine BTC and BCH, even if this question was pointed to Antpool or any other pool, my answer would remain the same, BCH does not support merged mining, it can't be "merged" as a secondary blockchain in the main BTC blockchain, other coins like NMC, SYS and EMC are merge-capable, and any pool that mines those merged coins can't hide it, the block header of those coins will be recorded in the BTC block itself, publically available for anyone to see.
Now some people who know the above technical fact will automatically think you are asking if "CK is stealing hashrate to mine other coins" which is probably why you got some harsh comments, however, if he was to steal say half of the hashrate pointed to his pool he could just mine BTC on another pool, do we know for certain that CK or any other solo pool isn't stealing your hashrate? there is technically no guaranteed solution to tackle this issue, it's either you trust the pool operator or you don't.
This leads us to why I told you (or the other guy) who started a solo mining pool that it likely won't work, when mining to a solo pool you need to trust the operator 100%, or else, you are going to be risking both your hashrate and the block you find, so nobody in their right mind would leave trusted pool that paid a dozen of blocks before and join a new pool which we don't even know if it's technically able to find blocks, let alone the trust issue itself.