RHEL Datacenter licence / virt-who - Satellite empty activation key

Hello,

I'm using Red Hat Satellite 6.2.11 with virt-who to register guest VMware VM.

I'm looking for a simple way to register a guest VM without adding RHEL datacenter on each ESX servers (because we have 600 ESX).
The recommanded way seems to create an empty activation key so Satellite could pick the appropriate subscription (https://access.redhat.com/discussions/2189341).
However, it doesn't pick the appropriate subscription : I have OpenShift Container Platform, Standard (1-2 Sockets) and that's the one it picks instead of Red Hat Enterprise Linux for Virtual Datacenters, Standard on the virt-who host.
Is there a way to exclude that licence from getting picked ?

Another issue is that there is only the OS repo activated on guest VM (but i could enable them later on the registration playbook).

Thank you for your help.

Best regards,
Samy Girard