This error usually indicates that the restore point is either missing required database files, is corrupted, or the backup session wasn't properly registered.
You can try selecting a different restore point (the one you used may be invalid or incomplete). Alternatively, try exporting the database files manually using Guest File Restore to extract the mdf/ldf files, or generate a .bak file.
I saw similar errors reported in the Forums..though not exactly your error, and there may just be an issue with SQL restores. One of them noted SQL restore may be a new bug, but there was not yet a resolution posted.
I agree with Chris...it would be best to open a Support case with Veeam.