Thank you very much for your time and idea.
Your suggestion might work, but - when I click on the data point, can see all options (Drill to Target 1, Drill to Target 2). I only need the action to be shown that is logically tied to the actual metric displayed.
So if parameter = Metric 1, then when I click the data pont, the only available drill should be to Target 1 because this is what is required there. If parameter = Metric 2, then when I click the data pont, the only available drill should be to Target 2, etc.
Is there a way?