The National Archives come through again!
I just discovered this wonderful pic in the public domain of Capt. Simpson's crossing of the Carson on his successful exploration of a new route across Nevada (that was almost immediately put to use by the Pony Express!) This is just on the northeast edge of what is now Carson City heading up river towards Genoa, then still Utah Territory. Elinor, Jane Vaughan, John and John S. Lewis would have known this site and perhaps crossed here.