I've opened a ticket with support. They gathered a bunch of logs and the only thing they could tell me was that the provisioning process was not able to contact the domain controller or create the account. They were not able to tell me which of those 2 it was. They were also not able to tell me what DC it tried to connect to. As you can tell it was not very helpful.
We do have 1 Read Only DC in our DMZ. There are 3 DC's in the same AD site as our Horizon View environment so I would not expect Horizon to try to create the machine against the Read Only DC, but I guess it's possible. So we created an ACL on the switch blocking the view environment from connecting to the RO DC just in case that was the issue.
Other than that we don't have any idea of what caused the issue in the first place. Of course we'd like to prevent it from happening, but in case it does I'd still like to receive an alert somehow.