Whether it is valid or not to talk about an employee's manager's cost center isn't the point here

Actually, it is exactly the point. At least as I see it.

You are in a piece of code where you find yourself needing to access an attribute of an attribute.

You are aware that by doing so, you are breaking the LoD.

The question you asked is: How can you legitimise the need to break the LoD, by wrapping it into a method that conceals the fact that you are accessing the attribute of an attribute.

But, if you re-read your post, you'll see that all of the methods you outlined, still access the attribute of an attribute; and so, still break the Law of Demeter.

The problem lies not in the implementation that allows you to do it, but in the design that requires you to do it.

My extended example was an attempt to show how such bad designs come about and why they are wrong.

An attempt to show that any of the solutions you presented, or any solution thatcould be presented, that continued to allow you to apply the value of a Manager attribute, in the context of an Employee, would continue to break the Law of Demeter.