Feed from custom tag – howto?

I have a extension from woothemes which gives me a product listing by vendor/artist. I can open that page with all products from that artist, as I use the vendors plugin for artists. All is fine, except if I call that url, the feed option does not work. Is there a way to make a feed work, if I use a filter something else in my function.php of Enfold?

Here is my example:

https://bildmanufaktur-wackernah.de/artist/ilona-weinhold-wackernah/
give me product page with all products from that artist. But if I call this:

https://bildmanufaktur-wackernah.de/artist/ilona-weinhold-wackernah/feed/
anything happens.

The permalink “artist” comes from the woocommerce extension product vendors. But they didn’t help me.