Is this even possible? I have 2 vault instances installed in the cluster. I looked in annotations, but I could not find anywhere how to tell the injector vault instance to inject secrets from. Will it always inject from vault instance that was installed first?
Before I can assist you with your issue, I have to ask a couple of questions.
Are your two Vault instances a cluster or standalone from each other? Are they running on the same Kubernetes environment or someplace else?