I've stopped using coinmarketcap myself, coingecko is one of the better alternatives that I have been using. CMC has shown to be untrustworthy by advertising crypto scams and showing fake volume.
That is a really bad situation and what you did is what customers should do and probably mail them or let them know somehow what they are doing wrong.
They shouldn't be advertising scams at all, they should hire people and set up a process that checks those projects but if they show fake volume for real then they are probably not that good people. Just have to find much more honest ones.