I have several custom fields, all defined to screens and projects. Some of them are available to display in Jira Plans and a couple are not. I have tried everything I can think of to get these additional custom fields to show up on our roadmap.
When I try to add a custom field to Jira Plans (Roadmap), this is what I see. As you can see, the field called "prioritization score" is not on the list.

This one shows up:

This one doesn't:
