OTBI Report that References Results of another OTBI

Summary

Is there a way to have one OTBI report reference the results from another OTBI report?

Content

Hi All,

Our use case:  We need an OTBI Contractor report that also identified if the contractor was ever an employee.

We have built an OTBI report that returns Contractor only info (using Workforce Management - Worker Assignment Real Time)
I would like to add a column (some identifier like a Y/N flag) to this Contractor Report to indicate if the contractor was previously (at any point in time) an employee. 
I'm not sure if this is possible, but my thinking was to build another OTBI that returns all employee assignment rows (active and inactive) and then some how have the Contractor OTBI use the results from the Employee OTBI as a lookup to check if the contractor id exists in the employee list.