CH does not do cost reallocation for Customers having master billing account with multiple sub billing accounts.

This is intentional as CloudHealth does not want to reallocate cost to all projects in case there are multiple billing accounts. 

CloudHealth does, however, pass down this billing account level cost in our Partner Generated Billing (PGB) flow.  Cost reallocation for channel customer tenants having billing accounts without any sub accounts in them will see the unknown costs reallocated.