I previously had FIOS but was unable to use my router at the time(night hawk x3) and verizon told me the samething that I wasn't able to use it due to their coding. However, currently FIOS is giving me a better deal and Informed the sales rep who helped me about my router. They stated that FIOS quantum would work with my current router - So seeing as I'm not the only one who's probably going through this or has asked this before I figured the community would be able to help me.
My router currently is Linksys EA9500 which was recently released and is a HELL OF A BEAST! so you see why I would rather use my router. If I can not use my router, I'll probably cancel the switch.
https://www.amazon.com/Linksys-Max-Stream-MU-MIMO-Tri-Band-EA9500/dp/B017NT8Q24 ( < - router)