Lauren,
Welcome to the forum! As you probably have already seen, there are lots of great folks here not shy about sharing their experiences with all types of treatment..
I didn't have middle fossa, however from what I've seen many have had great outcomes with that approach..
I believe the thought that radiation is bad based on your relatively young age has been debunked both by members here and by credible radiation oncologists that are familiar with using radiation for the treatment of ANs. With that said, given that you suffer from vertigo now, that gives me pause for using radiation as a treatment because it's not likely to get better (from what I've read about here), however with surgery (any of the 3 main approaches) it's very likely to get better.
No matter the treatment, all of those "serious side effects" are a possibility.. So, choosing one approach over the other may infantesibly affect your chances for having that kind of side effect. Aside from hearing preservation, that is. As you know, with translab your hearing will be gone no question.. With retrosigmoid and middle fossa approaches, there is a theoretical chance of saving your hearing... (same with radiation, btw). You run that risk for those "side effects" no matter the treatment choice (surgery or radiation, translab, retrosig or middle fossa, etc..). Sure the statistical chance varies slightly with each approach, however it's not a great change between them.
At the current size, I think watch and wait is very appropriate unless the vertigo becomes unmanageable.. It's great that you already know sign language and I assume you already know how to read lips.. That will be an advantage for you, I think.
Again, welcome to the forum.. we're glad you found us!
Regards,
Brian