When I saw "VM" and "backup" and "SQL won't start" it reminds me of an incident a few months ago. I'll pass this along in case it helps.
One of our developers needed a test environment of an already existing production SQL Server. The production SQL Server was a VM, so the VM administrator made a clone of the production server, renamed it, and declared it ready to go. When the developer tried to use it, he couldn't access SQL Server. I logged in and saw that SQL Server looked like it was installed, but was not running. I got the same error mentioned here and also could not get anything meaningful from the SQL logs.
I tried a couple of things to get it running but couldn't get it to budge. I then tried a repair installation, which also failed. The end result was that I had to completely un-install SQL Server from this VM and re-install. Once it was re-installed and service packs applied, I was able to attach the databases and it has been working ever since.
It seemed to me like there was something about the "cloning" of the VM that missed something critical to SQL Server.