I suspect they think the tests are unnecessary to determine whether or not you need surgery, since you obviously do. The PH test certainly could be done without, but I'm wondering about the manometry...only as a measure of your swallowing abilities. Perhaps with the large hernia you can't be measured in that way. The manometry is helpful because it lets the surgeon know whether or not you have swallowing issues, thus determining if he/she'll do a full or partial (for swallowing issues) wrap.
Good luck with everything!
Words of wisdom by Eckhart Tolle:
"Whatever you fight, you strengthen, and what you resist, persists.”
“Worry pretends to be necessary but serves no useful purpose”
“Accept - then act. Whatever the present moment contains, accept it as if you had chosen it. Always work with it, not against it.”