The thing is that it's VMware's licensing that prohibits using the backup API on the free version.
This is the reason that originally, Veeam supplied ESXi Free backup support - then had to remove that feature.
Scripts like ghettovcb are, as the name implies, community created hacks. They work great for certain scenarios but you have to realise there's a reason there's going to be limitations.
Surely the idea of shutting a server down every night to perform a backup is an amazing legacy that should dissapear with the stone ages. This is why "SCP" based solutions really aren't appropriate.
If I understand you correctly - what you want is a DR solution more than a backup. Consider the Virtual Storage Appliance to mirror those servers across your two platforms? It's not 'free' but if you consider buying basic VMware licenses for any other solution, you're pretty much there.