When I built https://hivedex.io I also made proper APIs targeted towards both coingecko and cmc according to their documentations. In order to have the HIVE/HBD volume tracked, they first needed an exchange to be listed. So hivedex.io had to be listed for them to track hive/hbd. I did build all the APIs and they didn't list anything. I remember crimsonclad also following up which resulted in nothing.

I did remove the old APIs I built for them in favor of a more decentralized API which is hosted on both of the following:
https://hafsql-api.mahdiyari.info/#tag/market
https://rpc.mahdiyari.info/hafsql/#tag/market

The above API is a complete market API and should satisfy any listing.