This topic has been posted for years, and the most recent posts have no responses. (My feelings won't get hurt if this post falls into that category)
In 2016, this post appears with an instructional video that describes a procedure however, the operations dashboard version used isn't available anymore. Back in 2015, Andrew Hargreaves added a comment to this post basically describing the method shown in the 2016 video.
So here we are, in 2019 and it appears that related data isn't even on the dashboard radar anymore.
Here is my work case: I have a polygon of zipcodes for my area of interest, along with a table of Meals On Wheels deliveries. I've created a relationship class between the Zipcode polygons to the delivery data( 1:m ) I've published that data (both feature class and table) as a Map Image layer as well as a Feature layer to our internal portal. And that's where the trail goes cold. It would be cool in Operations Dashboard to filter the related data by a deliver date range to gauge a trend month to month, or look at March 2018 and then at March 2019 deliveries to see any change in a given area of the map.
Wishful thinking? On the drawing board? Currently available?