"if I chose to do all the training in a ME."
I'm still not sold on the cost/benefit ratio of "doing all your training in an ME". Also, I wouldn't let a promise to get hired sway my decision. CFI jobs aren't that hard to come by and there are other ways to build multi time that might make more sense than "doing all your training in a twin".
An exception would be if you REALLY want to work at this place after you get your ratings, as opposed to maybe chasing around the country for a job. I never had any problems with being tied to a certain area, but not everyone is like that.