Loose Rivets
I appreciate that you are concerned, but this is a relatively common and straightforward problem. I dont understand about ablation and your daughter is on the young side but obgraham is on the ball with his advice.
You do not need to go to Geneva nor anywhere else so please ignore bizarre postings. The initial management is to use drugs to block the excessive thyroid hormones and this is normally well tolerated. That is obviously only a blocking mechanism so you then need to stop the additional hormones permanently either by removing thyroid tissue surgically or knocking it off with radioactive iodine. I would advise you to sit down with the paediatrician, endocrinologist and surgeon and go through relative benefits and risks to come to a decision.
Surgery is straight forward - we often do 3 in a morning, Home the next day, and some patients do not need thyroid replacement therapy. However, it really is taking a tablet once a day and having a blood test every 3 months. In the UK the family doctor does it, not a specialist.
The issue of T3 vs T4 is irrelevant at this stage. We do use both, but only one or the other for a particular patient. It does not matter that we dont replace both.
The concept of a fully monitored feedback system is a bit off track. True the regulation is pretty high powered, but the thyroid hormones are long acting and dont go up and down minute to minute. So taking one tablet a day really does fully replace it.
You would be surprised how many older people need thyroid replacement when the gland wears out! Please put this to one side and sit down with all the relevant doctors to decide on which treatment fits best.
PMs welcome