Unable to read directory role policy rules after assigning activation approvers

Describe the bug
Microsoft Graph is returning a 500 error with no code in message when trying to access role policy rules after assigning approvers in Entra Admin Portal.

To Reproduce
This uses the now-defunct "Kaizala Adminstrator" role, for testing (role id 74ef975b-6605-40af-a5d2-b9539d836353)

1. Added activation approvers approvers to role via Entra admin portal UI in "role settings"
2. GOOD: Can see policy assignment for this role:

• GET https://graph.microsoft.com/v1.0/policies/roleManagementPolicyAssignments?$filter=scopeId+eq+'/'+and+scopeType+eq+'DirectoryRole'+and+roleDefinitionId+eq+'74ef975b-6605-40af-a5d2-b9539d836353'&$expand=policy
• returns expected policy and policy id, has last modifled details

3. BAD: Can no longer see policy rules for this role:
   • Either of the following now fail with 500 error:
     1. GET https://graph.microsoft.com/v1.0/policies/roleManagementPolicies/{policy_id}/rules
     2. GET https://graph.microsoft.com/v1.0/policies/roleManagementPolicyAssignments?$filter=scopeId+eq+'/'+and+scopeType+eq+'DirectoryRole'+and+roleDefinitionId+eq+'74ef975b-6605-40af-a5d2-b9539d836353'&$expand=policy($expand=rules)
   • returns a 500 error, no error code, with the description "An error has occurred."
   • other roles and policies can still be accessed.
   • Entra portal now displays "An error has occurred" when accessing role settings for this role.

Expected behavior
Expected list of policy rules

Desktop (please complete the following information):

• OS: Windows 11
• Browser: Microsoft Edge
• Version: 149.0.4022.69

Start by reproducing the two Microsoft Graph requests against the role policy assignment and policy rules endpoints using role ID 74ef975b-6605-40af-a5d2-b9539d836353. Compare their responses with other roles and policies, and review the Graph Explorer handling for these requests. Done means the affected policy rules can be retrieved or the service failure is clearly documented with reproducible evidence.