As far as I'm concerned, franchises rent the blue oval from Ford like a sponsorship. They have Ford training schemes no doubt as Ford won't sponsor them unless they demonstrate a certain level of 'expertise' since Ford relies on reputation to compete.
But over time, it all starts to dilute and you get to this point.
Mr Belly was a member on here some years back and he dropped sticks and went over to vw, he had a similar case to yours.
Ford franchises base performance on turnover, they charged me 200 pounds to change the oil and filters on my van, so 30 mins.
They did a full health check but they didn't do it all as I know some info they wrote wasn't 100% accurate.
I also don't see any disturbance in the oil filler dust it is dry which suggests that the cap wasn't removed and I can't prove it but in not convinced that the oil was replaced
but it is on 16500 miles so not critical as I changed it at 4800.
That's all irrelevant to your question though, i elected to fix my own van, i dare say that if I continued driving it with that faulty injector as recommended by the Ford mastertech, I may well have been looking at over fueling and possibly damage to cylinders?? Who knows
You have 2 options.
Kick up a fuss and try gaining some leverage with Ford head office, force the dealer to either get on it or change dealer.
Or get an independent on to it and try billing Ford (be careful with that).
But you just want a diagnosis for now which if Ford can't do then what??
I bet they will have had a quick look and not found it then put it on the bench for when they've got nothing on.
Do you have any inclination as to the noise?
Ps. How long have you had the van? If you've only had it just before you sent it in then I'd probably be sat in front of the salesman with the keys and logbook if I thought it was seriously faulty.