Oh dear, poor you and poor dd.
We did make a complaint, although ours was tied in with lack of SALT, and this was bfore his diagnosis of di-george syndrome.
DS2 was first noticed to have hearing problems at his 2yr check, he was already under the hospital for resp infections, failure to thrive etc. He was ref to ENT and had his first lot of grommits and his adenoids removed. No improvement and six months later (just after his third birthday) after several severe bouts of tonsilitus that left him hospitalised, he had his tonsils removed and an ABR hearing test done whilst under the GA>
When we went back two weeks later to ENT they told us that his hearing loss was purely down to glue ear and that his grommets, that had come out had been replaced and all should be well.
Six months later, still no improvement with speech or hearing we go back for routine check to see a different doctor who asked us how he was getting on with his hearing aids, and was reprimanding us for ds not wearing them. It transpired that we had been given incorrect info and that ds did in fact have a sensorinueral loss in both ears and would always need hearing aids. I can clearly remember how furious and distressed we were at wasted time so you have my sympathy.
We wrote to the cheif exec of PCT and copied it into the head of SALT services, the senior manager of hearing services and our local MP. We actually didn't get his notes but you could request them. If you are I would suggest doing this before you put in your complaint.
The complaint was resovled in terms that we got an apology and actually very good SALT services since and we had a meeting with the cheif exec of the PCT. That in itself made us feel better.
A year later we get his diagnosis and find out that he has a type of cleft palate and should never have had his adenoids removed, and because of this he has had to have major surgery on his palate and will do again in the near future. AAAAARRRGHHHHH!
It really depends on what you want to achieve from your complaint I guess, for us at the time an apology and the chance to rant was enough for us.
Good luck and sorry for my rant!