This seems to be working for us:
We have Quickbooks (2018 multi-user) hosted on a PC. The QB file(s) is local (within a documents folder on C) We OneDrive set to backup/sync the entire Documents folder. I turned OFF the option to have "Files On-Demand" so that the files stay local and also backup to Onedrive.
As a secondary, we perform a daily QB Backup to Google Drive (MyDrive) folder.
