Download link forming and homepage redirection

Background to issue:
I’ve been trying to get Download Monitor files to appear in searches, and it’s been very tricky.

Right now I’m trying out SearchWP, who recommends adding some code to functions.php to make our downloads searchable. We’ve done this.

So now, downloads ARE showing up in search results. Example Search. “Alcohol Risk Management Module” is a download result.

However: the problem is when we click on a download link from a search result, the visitor is redirected to the homepage.

The download links from the search result are formatted like this:
https://mjsorority.com/?post_type=dlm_download&p=771 (This doesn’t work, it redirects to homepage)

But the download link from download monitor’s own output is formed like this:
https://mjsorority.com/download/771/ (This works, and the file is downloaded.)

Permalinks on the site are set to “post name” and are not custom.

Is there a way we can make this work?

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