MOSFET's usually fail and damage injectors. I hope you replaced all of the mosfets, not just the failed one. The person doing the repair should have used an air station, not an iron, if they used an iron 9/10 chance they ruined something. These things are important for a proper repair.
Yea, all mosfets were replaced. Not certain regarding equipment used as my buddy dealt with that. I've used him in the past to repair a pin in my dme that became recessed. Probably lucky I didn't have additional issues as an iron was used at the time.