While big centralized exchanges will likely not give support to these tokens, still I believe that liquidity could be found within smaller exchanges and on Defi services.
The key for these tokens to survive the bear market is their respective casinos not to give up on them and continue to support them through the low prices, there will be people gambling during both bear and bull markets, so it is within the objectives of those casinos to give enough reasons to their gamblers to buy tokens.
Also, Exchanges like Binance have given support and listed tokens of dubious reputation in the past, if a famous/big enough casino decided to do business with Binance, they could manage to get their token listed.
To take these tokens to the big stage, there is no other option but development. Listing on low volume exchanges will not benefit you but may create a worse reputation due to manipulators. Therefore, these projects should be regularly developed and take the project to such a level that it catches the attention of big investors. When big investors get involved by investing in a project, many difficult roads will become easier. And there are many reputable casinos in the market so if they force their customers to buy tokens then that will not bring good results either.
Development and proper marketing are very important to build a strong position in the market, and no matter how hard they try, it will be difficult to stop the dumping of these tokens.