Sadly to say DL staff didn't write me back several years ago.
I don't have the strong impression that someone is able to recover a deleted single course from a backup server, not even if you noticed it within 1-2 days.
I wasn't able to regain the strength to restart my reverse DE-EN tree and to re-test out where I had left off.
You could open a ticket and try your luck, but somewhere it's written that "gone is gone".
I offered them a PayPal donation. I may have enrolled into Duolingo Plus for one year.
Doesn't seem anything was possible as they've NEVER reacted.
In this AI century you probably know that your chances are much less that someone human reads your ticket, sadly to say.
Maybe try contacting a DL staff member on the /r/Duolingo Reddit channel directly once you've opened a ticket_id.
But without telling them precisely when this has exactly happened that 1-n courses are suddenly gone from the learning list they wouldn't have a clue to what date to rollback some profile/data changes.
And the backup on a second server might not do an incremental backup for 30-90 days.
After x days they might overwrite some old data.
As I said, I immediately contacted them the same day; not any chance.
Your Super subscription might not be enough that someone has to dig through file based backups trying to recover any lost DB entries; it's a big job, consuming some man power hours.
If I shall guess: There's no admin tool supporting this automatically.
They didn't think so far, else there would be an automatic restore button, asking you for which date and language pair in the last 10-30 days.
But if you feel any better when you have at least asked them to do this, go for it.