Guest VM is not created intermittently and the following errors are observed in controller.log with extended logging enabled:
Code 8557 means the following:
"Your computer could not be joined to the domain. You have exceeded the maximum number of computer accounts you are allowed to create in this domain. Contact your system administrator to have this limit reset or increased."
In this case function NetProvisionComputerAccount fails to return any data and produces error.
Use a different Domain Admin account in template VM configuration or clear the corresponding counter for the current account.