This same thing is happening to me. I’ve only submitted one sitemap, but it contains two additional sitemaps. Which is the exact same situation the OP is experiencing. One of the sitemap’s has been processed, and the other is saying “can’t fetch” due to a ‘noindex’ detected in ‘X-Robots-Tag’ https header.
My structure looks like this:
1. /sitemap_index.xml
1a. /page-sitemap.xml
1b. /rem_proeprty-sitemap.xml
The /page-sitemap.xml was able to process just fine, but the /rem_property-sitemap.xml says it’s unable to fetch.
