What happens if Date Cleared or Time Cleared aren't null? Your requirements aren't very clear.
Well, this is one of those cases where using Measure Name in a calculation would be handy. Vote for this: Measure Names/Values Variables...
Oh well. So the syntax for the first part of your calc is:
IF ISNULL([Date Cleared]) AND ISNULL( [Time Cleared]) THEN ...
You'll need to create one of these calculations for each of your three dimensions. Then you can use Measure Name/Value to set up your viz.