File recovery when files manually added to ../nextcloud/data

I have a problem that seems like it should be straightforward to fix, but so far I seem to be dumb, here goes:

I had a Nextcloud 12 VM running in Openstack. I did something dumb and the VM became unbootable.
I used some utilities to mount the virtual disk and copied out my /var/www/html/nextcloud/data directory, I have been able to open the files normally.
I spun up a new Nextcloud VM from the starter image I’ve been using, recreated my 2 users, and copied the backup …/data to the new VM’s /var/www/html/nextcloud/data, files SCP’d from the new location open normally.
chown -R apache:apache /var/www/html/nextcloud/
Ran sudo -u apache php /var/www/html/nextcloud/occ files:scan --all
The two users I have can log in to the webui and the folder/file structure appears normally in Nextcloud, but clicking a file to open it brings me to a Nextcloud Service Unavailable page.
If I scp those exact files back out, and upload them from the webui to a “test” folder, I can access them normally, so I have a (crappy) way to fix this, but honestly I just want to understand what the problem is.

*Edit: fixed a typo