It sounds like you have been through a lot. I hope you are holding up OK.
This is not a very common procedure for IIH. I have only been diagnosed for a year and although i have heard of the procedure I have not yet heard from anyone who has had it done. But I am by no means all knowing, hopefully someone will be able to get back to you with some personal experience, or someone who had it done for a similar condition to IIH.
I can offer some credible research papers for general information.
This paper was published by the American Journal of Neuroradiology in 2003 and it outlines the relationship of raised in general ICP to the Jugular Foramen.http://www.ajnr.org/content/24/1/45.full.pdf
And here is an abstract that deals with hydrocephalus (another condition where the body produces too much CSF that significantly raises ICP) where a child was treated by jugular Foramen decompression. This is encouraging, hydrocephalus can be a life threatening increase in ICP, so the procedure very has good potential. http://www.ncbi.nlm.nih.gov/pubmed/2352015?dopt=Abstract
Other then that i would suggest you take a big sheet of paper and write down all the questions you can think of and then see if there is a patient liaison service, with your hospital / doctors. or can you book an extra pre-op appointment to ask any questions you might have, if you dont find all the answers you need here. Most places expect you to have questions and it is your right to have all your questions answered well in advance - even silly ones: will you have to shave my hair, will i still be able to wear earrings, and not so silly ones: do you have to put a stent in? what complications can there be? will i still need IIH drugs after? does anesthetic effect IIH?
Best of luck, hope everything goes well for you!