Welcome to the GERD board! Sorry you are having throat discomfort!
I've heard that after surgery like yours, many people have heartburn return anywhere from 5 to 10 years after the procedure (depressing, huh?). But having never had it myself, I can't say that's fact for sure. I'd talk to your doctor and see if that's a normal occurance. Also can't advise on a second surgery, as I've never had a first, but that's not to say they can't perform a different procedure to get the results you want.
Concerning the Prevacid, I've been on this medicine before, but it was to treat heartburn only. I've never had sore throats due to acid. I would think two weeks' time would be sufficient to tell if it is going to work. It doesn't appear to be helping you much at all.
I also suggest seeing a gastroenterologist, simply because this (among other conditions) is their specialty. He may be able to see things your ENT might not, as well as suggest other remedies/solutions.
I hope you feel better real soon! Please keep us updated!
And days go by
I can feel them flying
Like a hand out the window in the wind
And cars go by
Yeah it's all we've been given
So you better start living right now
Cause days go by