No way to add indexed content when global settings are no-index

Hey guys,
Long time fan and Yoast groupie. I’m splitting content in a custom post type, some of which will be indexed but the majority not. I’ve set the global custom post type visibility settings to “show posts in search results – no” which has done the job and no-indexed the bulk of the content. However when I set the desired custom posts to index they don’t show up in the sitemap file because the global settings are blocking it off. I found some resources to exclude additional items from the sitemap, but nothing to add something back in. Did you happen to have any knowledge base resources that cover this area? Or would you recommend putting together a custom sitemap file for these posts?
Thanks in advance for your time.
Warm regards,