GCC Sandbox Tenant for testing changes outside of production tenant?

Microsoft has a developer program that offers a licensed tenant designed for Azure development work and testing, but it is not relevant to GCC work.

There will be many features that will be enabled in this tenant that will work differently or not be available at all for GCC tenants.

We already have a GCC tenant, but it is not safe to “test” in our live tenant.  We can add a second directory for testing, but then it has no licensing.  So, we would not be able test anything requiring licensing and we are not able to purchase licensing just for testing.

Is there a process to get no cost licensing for a secondary GCC tenant used for development and testing?

Since the test tenant doesn’t physically need to be in the GCC cloud and only needs to act like at GCC tenant, is there any method to use the existing developer Azure tenant program and configure it to function like a real GCC tenant would?