Good question. It's not obvious why a page would be included in a group that "needs improvement" but be individually assessed as having "good" CWV.
In short, Search Console is grouping pages by similarity and reporting on the aggregate quality of experience over the entire group, not individual pages. So the aggregate LCP user experience over all pages in the group is evaluated as "needs improvement". Individually, PageSpeed Insights assesses the page as having a "good" LCP.
According to the Search Console docs
: "An issue is assigned to a group of URLs that provide a similar user experience. This is because it is assumed that performance issues in similar pages is probably due to the same underlying problem, such as a common slow-loading feature in the pages."
I'm not sure how you've implemented each page in the "Similar URLs" list and how much they actually share the same features. Perhaps /rooms is being incorrectly grouped with the other pages? Let me know if that's the case and I can pass that feedback along to the appropriate team.
Hope this was helpful.