That hasn't prevented quite a few popular exchanges from offering it though. I mean Kraken and Bittrex aren't exactly small exchanges.
I'm sure that in the near future a couple of casino's will start accepting Bitcoin cash. The price is getting a little bit more stable now.
I don't think stability in price will play significant role in casino decision to add support for bitcoin cash. What most of the casino might be waiting is quicker blocks and demand from their users for bitcoincash. Bitcoin cash is just like bitcoin except its price and mining difficulty, fees are comparitively low but that is only due to low price per BCH.
Yes we might see some gambling platform adding them as a payment method in near future.
Yup stability is not mattered because bitcoin and other altcoins also not have stability in price. But all casinos are accepting these altcoins. BCH is a new coin, so it takes some time to implement. And also depends on users, if the players demand this coins then casinos will give priority and accept or else it takes some time.