Can the Vault stanza be specified multiple times, each with a different namespace and create_from_role option?
Is this similar to what you’re looking for?
If so, the answer is yes, but for a price.
This could be misleading:
Multiple stanzas meaning multiple Vault instances or multiple stanzes with one Vault instance with namespaces? And if the last option, I guess you’ll need Vault Enterprise, too. Beside Nomad Enterprise.