Congrats!
Maybe in the supplemental information of the application, write that you received an offer from an employer for GEM and state which one. You could also call the GEM rep at the school you are applying to and let them know.
Would it be possible to share which employer?
I agree with @horizons I've heard/read the same. Has anyone called GEM to ask questions? Was the experience positive? I feel like I might have just called on a bad day.