temey74938 I don't think so, no. But if you have an external script or service handing that, you could use this extension to redirect first to that intermediate URL EDIT: I thought this was the general affiliation generator extension. In this one it's not possible to configure a redirect.
I've never used that Genious thing. If they have an URL redirect service, you could do what I described in the first paragraph.
If you want to use their javascript library, you will likely need to use the Flarum extension API to run the code every time a post is rendered, essentially creating a new extension.