We have been listed a long time now at BitexLive and so far I have never heard of any problems from the community.

I checked the block explorer and it does show your 20,000 coins are at the address you shared - https://blockexplorer.roi-coin.com/address/RREm6WzBtvUTPkuWuo9qsZ6x93f1WWx6YA

If you don't see the coins in your account at the exchange I would say give BitexLive a support request you can DM them at Twitter or contact them through the website.

Let me know if you have trouble getting it resolved.