Verdi is home to two of the closest Nevada casinos and RV parks to California on I-80: Terrible's Gold Ranch Casino, now known simply as Gold Ranch Casino, at Exit 2 and the Boomtown Reno at Exit 4. Nearby is the closest Cabela's to California.
Optus / Vodafone do share, but they are going their own ways. However new towers may still be built for both. Vodafone / Telstra have roaming capabilities using Telstra towers in some areas Hutchinson (3) / Vodafone have some shared towers Telstra / Hutchinson share towers
In a real emergency cell towers can be down and as anyone who owns a cell will tell you even at the best of times they will not work when you need them! There is one option that has been used for over 100 years and that's longer than we've been alive. That's HAM radio or amateur radio.