I think with this example solve the problem that you want to achieve.
You need to change the data model adding a dimensional KPI doing a full outer join with a new dimension and create a field with the value for each of the KPIs.
To do the join in tableau is tricky and then you need create a constant in the dimensional table and join with the same constant in a custom join.
Thanks Cristian. It's an innovative way to make it work! You will achieve 100% if you can make (1) the format is more flexible - say gross margin %) and (2) the solution is scalable.