Does Stuck options “–ssh-fingerprint” help any? If not, what’s the storage type now, and was it once SFTP?
You could also view that job in Commandline mode, and have your web browser search for fingerprint uses. Searching that way is just a simplification to avoid you going through “Target URL” and “Advanced options”.
You can also just change nothing and run a “backup” from Commandline. Output might even help discover whatever’s going on, because you can view the backup action directly, instead of it being collected for later.
Your final comment sounds like trying to find a flag to turn this off. I’m trying to find the flag that turned it on.