I have 2 worksheets those were created from 2 different data sources that I would like to place on 1 dashboard. Each worksheet has 3 sets of parameter controls: "Provider", "Start date", "End Date". The data sources are set up slightly differently, so the "provider", "start date", and "end date" parameters are not identical between the 2 worksheets (they have different names, were calculated differently, etc.). I would like to put both worksheets on to one dashboard but I would like my users to see only 1 set of controls that would control both worksheets at once. I cannot seem to figure out how to do this.

Parameter works for a particular worksheet. If you have two different data sources in a workbook and based upon the different data sources you have created different worksheets then you might need to combine them in the dashboard. but as you mentioned you are using a calculated field in the filter and so your work will be a little easier. I would recommend you to use the parameter in the calculated field itself and not separately. this way you can achieve your desired result. you can write the code something like below-

Data Source 1:

If [FAC]=[Facility] then sum([Number of Records]) end

Data Source 2:

If [FAC2]=[Facility] then sum(Number of Records]) end