Custom URL in Link Display in RSS Feed display is overridden by path set in Page display

I have a view with a Page, RSS Feed, some Panes and some Blocks. I want to pull the Feed into another site where a linked Title is created using the Feed's link (xml:base). I can set the xml:base using Link Display to either page or feed, but I want to be able to use Custom URL. I can't use 'page' because I've got a contextual filter in my Page display so it outputs as https://www.site.com/blog/%2A/%2A. The Custom URL doesn't change anything; it continues to use the link from the Page.

I'm not sure if my issue is related to this one https://www.drupal.org/node/2180897 → . FWIW, the fix in that issue did not work for me.

Should I be able to change the xml:base with a Custom URL? I'm not sure if this is a bug or a feature request.

Thanks!