Not sure how you have this setup or what tool you are using to return these results, but if you are just querying the database you could do something like this:

SELECT Measures.[% Tasks Completed] on 0,

{Ancestor([Organisation].[Hierarchy Name].[Employee Name],[Organisation].[Hierarchy Name].[Team]),

[Organisation].[Hierarchy Name].[Employee Name]} on 1

FROM [Cube Name]

You would need to replace the hierarchy name, the employee name, and the cube name. Also, this is referencing the name of the member and not the unique name, so it might look like this with the unique member (or key) reference:

SELECT Measures.[% Tasks Completed] on 0,

{Ancestor([Organisation].[Hierarchy Name].&[Employee Number],[Organisation].[Hierarchy Name].[Team]),

[Organisation].[Hierarchy Name].&[Employee Number]} on 1

FROM [Cube Name]

By using the Ancestor function you can grab a related dimension member at a specified level in the hierarchy.

Ancestor (MDX)