It depends on what the dealer wrote in their estimate. If they wrote that they were going to replace the module, you’re technically out of luck since that’s the contract you signed.
If they indicated they were going to diagnose and fix the problem, they didn’t succeed. If that is the case, you paid them to fix the problem, not to take a gamble on what the problem might be.
It would be their risk, not yours.
I agree with Whitey’s idea but I would cc the Ford Regional Manager and everyone higher in the chain of command.
Also, I would not threaten them that you will take your business elsewhere. I would stick to the facts without placing the blame on them (they can figure that out) and mention that you have been a good customer and are unhappy with this particular service.
The strategy can work. My brother had a problem similar to yours and got good results using the above method.
It’s worth a try.
Good luck.