Hey Kitkat,
Hydrocephalus can have a number of causes and effects from stenosis of the aqueduct (narrowing of the aqueduct) all the way thru to a blood clot causing a blockage. Some causes can be congenital or prior to birth, some can be due to trauma. There is also a condition where it can be due to a lack of reabsorption of CFS within the brain. Depending on the cause will depend on your symptoms. I would have to agree with your specialist regarding the closed aqueduct and the brain developing another route to move the fluid. I say this because your brain produces around 1 pint (600ml) of CSF(Cerebral Spinal Fluid) daily. If that fluid cannot get out, eventually it can lead to a coma (worse case scenario) as there is only so much room within the skull. There must be a balance of CSF, blood and brain matter within the skull for everything to work in harmony. One thing out of balance can cause symptoms.
I have a growth within the 3rd ventricle, blocking the aqueduct. At first they did a CAT scan, which did not define the growth very well and they thought that the hydro may just have been caused by a simple blood clot. But upon completing an MRI with contrast dye it was found to be a bit more than a blood clot as the growth was more defined. I was told that depending on the location of the start of the growth would depend on the symptoms, which have been numerous over the years, many like yours ie fatigue, bladder infections, heart rate issues, etc
Personally, I'd be getting a flow study(and any other tests suggested) done. The more information you and your medical team have, the better and more defined your diagnosis will be. From there an appropriate treatment plan can be made if it is deemed necessary.

Good luck with it all and I hope you can get a bit more clarity from the drs. Keep us updated.

Merl1n