How can I get the original resource on the onEventMoved callback?

I have a job on the scheduler and multiple people may be assigned to the same job, I want to be able to find the original resource the job was assigned to when it is moved so I can replace the old resource with the new resource and cannot find a way to do this.
So does the args of onEventMoved return the original resource? or is there a way to expose it or grab it possibly when a user clicks but does not release?