Fistulas are sooooo hard to get rid of and sooooo annoying; I'm sorry you are dealing with one. Do investigate all options. I've recently discovered the "UpToDate" medical care summary through the Mayo Clinic (www.uptodate.com) and it has some great information. Technical, but in-depth.
I've had 3 porcine mesh repairs with multi-layer closures and this last time a "plasma plug". Unfortunately this has not worked for me, BUT I am apparently the only one of the original 10 women this particular technique was tried on who has not had success. The success rates are currently running in the 80-90% range, which is quite high. Just my luck, huh?
All that to say: do your homework, ask LOTS of questions, investigate everything. Make the decision that is best for you... And know you are not alone!