Wow, this has to be really frustrating for you sweetie! I feel for you! I will tell you that in my 20's, I had a health issue that did involve my thyroid and general hormones that was a two journey of figuring out the issue and recovering. And to give you hope, once my thyroid corrected itself, I have not had an issue since. I have my thyroid checked annually for any type of change and it hasn't changed since that time being completely normal. My cycle was every 3 to 5 months at that time and once it was all back to normal, I was regular again and have been ever since. So, things very often get better even though when you are in the throws of it, it seems like that will never happen.
But your thyroid has been deemed operating properly. So, that is good. It definitely can create the symptoms you have if it is working slower than it should and they smartly ruled that out.
So, my sister in law has narcolepsy WITHOUT cataplexy. It looks a little different than regular narcolepsy. https://www.sleepfoundation.org/narcolepsy/what-narcolepsy/are-there-different-types-narcolepsy She has a hard time staying awake during the day without medication. This is called type 2 narcolepsy as well.
My sister in law as I said takes medication that allows her to be functional during the day and go to work and drive and all of that important stuff. I do know she also has started wearing a cpap mask at night (oxygen).
I guess I'm wondering if you don't have two different things going on. I have also been in a situation of a hormonal imbalance and produced naturally too much estrogen. It was amazing how it affected so many things. So, I do not negate that your hormonal imbalance isn't also impacting things. Wondering if it isn't two separate issues though?
Hormones do greatly effect sleep. The issues surrounding perimenopausal women moving to post menopausal is well documented (in that phase myself). So, this article is excellent at describing that. https://www.shecares.com/hormones/progesterone/research/progesterone-hormones-cause-sleeping-problems
I would see if you can move up your appointment to earlier than 5 months. Balancing out your hormones seems imperative. And what about working with a nutritionist to try to work on that side of things to help? Sometimes the tricks of the nutritionist can give us a bump in our health and how our body is balanced.