Hey,
I don't think you will ever be able to solve this with retail keys. There are some options you can look into:
- Set up office in Shared Device mode and let users that log in activate Excel with their own Microsoft 365 subscription.
- Use device based licensing for Microsoft 365 apps for Enterprise. You can read more on this here: https://learn.microsoft.com/en-us/deployoffice/device-based-licensing
- Setup a KMS hos for activating office versions (Volume Licensing)