A FORD dealership certainly should have all of the electronic equipment needed to properly diagnose, AND REPAIR, any issue with your engine and electronic control unit.
The MAF is just one of many sensors that feed information to your ECU that allows it to adjust various systems so that your engine runs properly, with the right timing and air/fuel mixture.
It appears that you have found a dealership with a "mechanic" that prefers to just throw parts at your problem at your expense. I think it might be time to talk with someone in authority at the dealership and find out why THEY cannot properly diagnose the problem.
At Rockauto.com your Motorcraft MAF sells for about $170 and an ECU computer sells for around $200.