How to make a date ranger filter in dashboard only affect the numerator of a measure used in its own tile that divides two other measures?

As of now the filter affects both the numerator and denominator when I apply the filter to the tile that has the conversion rate (trials / visitors) measure. But, I would like the date range filter to only affect the numerator of the conversion rate measure i.e. only affects the trials measure.
I tried setting up a filter in the view the dashboard is using i.e.
filter: in the view (programmatically)
and I tried using this filter within the sql of a new hidden measure for the numerator (trials) of the conversion rate measure (trials / visitors), but I didn’t know how to get this new filter to appear in the dashboard filter section / how to retrieve the date range from the filter dynamically when the user updates the date range filter.
 
Any help on how to achieve this functionality would be greatly appreciated!