"recent files" don't show up under "all files"

Hi Brian, 

Welcome to the Box Community!

Box "All files" page is where you will see all files and folders you own and you have been invited to collaborate while your "Recents" page contains the files you've accessed, starting with the ones you've accessed most recently. This includes files opened in other Box applications or on other devices.

You may find files in recents such as those you opened from a Shared link that are not in your All files page if you are not a collaborator in that content.

To learn more on the difference between using a Shared links to access a content and being a Collaborator, please take a look at this article: https://support.box.com/hc/en-us/articles/360044196073-Collaboration-Frequently-Asked-Questions