As zomex pointed out,
If they list it free then the developer on his site charges for it, you simply need to wait for WHMCS to make their rounds and update. It is helpful to let the team know about it so they can jump on it like they do and correct the listing.
This is a new feature from inside WHMCS and I am sure something will be worked out for example:
If a developer of a addon lists it free then within a certain time charges for it and fails/forgets to notify the team then a suspension of being listed may be in place. That is an example, but possible. Maybe WHMCS shouldn't list it free or not and let people look into it to find out.