I think that the topic starter was referring to the enterprise and free versions of Discourse.
And even then, VirusTotal offers an API that is free to use, as can be read in Public vs Premium API :
The Public API, on the other hand, is a set of endpoints available for everyone to use at no cost. The only thing you need in order to use the Public API is to sign up to VirusTotal Community and obtain your API key as described in Getting started.
I don’t see how this could do any harm.