As a new landing page, it’s really hard to get found if you can’t have a sitemap. I have unbounce on the root of my domain, so there’s no apparent way to have a sitemap, so I’m stuck in the supplemental index.
Without sitemap there is no way I know of to ever get any organic search results with Unbounce.
Just like you can upload an image, there should just be a button to upload a sitemap. Or better yet, automatically generate it for me since it’s a rather simple XML file.