Hi Jonathan,
I have the same issue. I tried exactly the same as you explained but no luck.
The error message I have is as below;
"code":500,"details":null,"message":"Failed to export site. Failed to create the folder
However, I noticed that the backup utility creates the backup folder this way "WebGISSite1234567891236" > "datastore", "portal", "server > kocjnf3ojagyagzw" but when WEBGIS DR utility stops all the backup folders are removed automatically.
I'm on ArcGIS Enterprise version 10.8.
Any assistance will be highly appreciated.
Thanks
Abdul