I was looking for a yes or a no. I will assume all three jobs are on same system.
That’s a minimal test. You should at least be running BackendTester for awhile.
Also check for retry counts before deleting the job database (which deletes logs).
As long as the configuration matches the new name, job shouldn’t mind renames.
Extra unknown file: duplicati-bb7ad446be3d9414e9f37dca1b4e077f0.dblock.zip.aes.part
The key here is that your destination is apparently one that creates a .part file during upload, and doesn’t clean it up. If this is consistent, there’s your problem.
Your backup configuration is a little different though, but winds up the same way.
You can ask Magenta support to see if they comment on use of the .part files.
You can also set up the logs I mentioned to see if, for example, the Duplicati file:
duplicati-bb7ad446be3d9414e9f37dca1b4e077f0.dblock.zip.aes
had something go wrong during its upload, thereby leaving a .part file behind.
If you are able to query Magenta, maybe you can even observe such file usage.