So sorry to hear of your problems, it does sound as though you are having motility difficulties, did this show on any prior manometry that you have had?
I would think that a reputable. Consultant will send you for another manometry before even considering you for a nissen, with people who have motility problems they have to be careful they do not make it worse.
That is not to say its impossible to have surgery, they just have to be sure it's the best treatment for you. Have you looked at endostim it seems a better treatment for those with motility problems.
All the best,