I'm working on a similar task at the moment.
I can see that your output from the backup is to here:
\\\\hostingAGS1s\\e$\\WebGISSite1676308777997\\dataStore\\4xxxxxx9-xxxx-xxxx-xxxx-0a2ad801cff1
One of the things I've found on a client site is that there Data Store has blown out in size over the last few months and the backup is now taking in excess of 2 hours. We previously had the datastore backup at 1AM and the Webgisdr site backup at 3AM. However, the first backup isn't completed by then, so the webgisdr fails because of the same error message you've mentioned.
We are in the process of changin the output location of the backup so that it is on local disk (no network bottlenecks) to see if that speeds things up. The plan would then be to robocopy the output file to the same location on the remote disk.
I'll feedback if we see a noticeable improvement in performance for backing up locally. I should know in the next hour or so.
Scott Tansley
https://www.linkedin.com/in/scotttansley/