This accusation is grave mate. Although I have not tried it at your exchange but binance fee is normal and ok to go by but bkex charges seems too exorbitant and outrageous for such a fee payment.

However, your proof is not factual mate. What you have uploaded is not feasible for a proof to hold unto. I will advise you get good proof may screenshot it wherever it is written on their site then upload it here so we could see.

It is nice you did call the attention of members here so everyone could take caution but it would be ok for a better proof to be seen.