Hey @Boggin and welcome to the restic community! 
Thanks for sharing your Windows PowerShell script with us.
As a little side note and hint: I would add some VSS to your script so that you can make sure that even locked files can be backed up by your script.
This was already discussed on the forum; doing a search here: https://forum.restic.net/search?q=windows%20vss
I don’t think I have seen the use of the credential manager in any of the .ps scripts posted/shared on the forum, so I think this is a great addition!