Office 365 - Cannot Grant Permission To Manage Address Lists

So I'm trying to segment the GAL in O365 and I'm unable to assign the required permission to manage the address list. I get the following error:

"You don't have access to create,change, or remove the "mydomain.onmicrosoft.com\Address Lists-GAL Management" management role assignment. You must be assigned a delegating role assignment to the management role or its parent in the hierarchy without a scope restriction."

First is that I'm not trying to manage the '.onmicrosoft.com' domain, I'm trying to manage my own domain. Second, I've checked around and seen this fix recommended at least a dozen places:

Add-pssnapin Microsoft*

Install-CannedRbacRoles

Install-CannedRbacRoleAssignments

I'm able to run the first command ok, but the second and third commands return this error:

"The term 'Install-CannedRbacRoles' is not recognized as the name of a...