Sorry CP3P0, I clearly am bad at reading messages, just saw that you had mentioned you can't ssh into the host.
Since you can't actually ssh into the host, there is nothing much you can do.
I would probably check if right keys are being used and the username used is ubuntu (not root).
Apart from that, your best bet would be to reach out to the Veritas Sales rep that helped you with this. If this is something you tried on your own and you don't have a Sales rep, you can request a sales rep to call you and help you setup a Proof of Concept : https://www.veritas.com/form/requestacall/requestacall.html?cid=300000758729315
Hoping the issue is with SSH keys or the username :)
Cheers,
Ash