Google can’t index files in dlm_uploads directory as it is a protected directory witch prevents someone from downloading/viewing your files directly ( for example, from a media library URL ).
Tracking the number of downloads of a file using Download Monitor is only possible if a user clicks a Download Monitor link/button and goes trough our download process.
If you wish that the files are both indexed by google AND downloaded via Download Monitor, add the link to the file in the downloads BUT you won’t be able to track the direct downloads that don’t involve the Download Monitor’s process.
https://mysite.com/wp-content/uploads/2022/09/my_file.ext – this is a direct, indexable, link to a file stored in Media Library, if a user views/downloads your file using this link DLM can’t track the download even if you add this file to a download.
There is no way of allowing Google to index a file, protect it from being directly accessed, and tracking it’s number of downloads.