OK, so, if the only problem with Webmin is the System Information, I guess you can go try to restore the broken/missing features.
Since you started over from scratch with the httpd.conf (if I’d understood you didn’t actually delete the whole file I wouldn’t have suggested you do that…we’re behind where we started from, this is why we assess before we act), you’ll need to reconfigure it for Virtualmin before restoring anything to it:
virtualmin config-system --include Apache
Then in Virtualmin Re-Check configuration.
If all of that goes OK, you can then start restoring.
The VirtualHosts are found in the Apache webserver configuration and Apache SSL webserver configuration features in your backup (in the “Features and Settings” section of the restore form). I would not restore all features, since everything else seems fine. So, just choose “Only those selected below” and choose to restore the web server configuration.