Hi, @kpatel.
We just added new functionality to the URL redirects tool which allows you to leverage proxy redirects to host files on the root directory of your HubSpot-hosted site. (Although the announcement was on March 15, I was notified of factors that hampered your use case, so I held off on posting here until I got three green light today.)
Per this updated article:
Proxy: select this type to redirect the content of your live page without changing the URL displayed on the visitor’s web browser. This redirect type is often used to share a file that’s hosted on a specific directory outside your main site.
If I understand the request from your original post correctly:
Any marketers here who have issues of not being able to upload files on root directory?
… this change should solve for your use case.