I have not looked into this more, except that I have seen nothing in the model data to make me doubt the original conclusions. I am not aware of any actual observations for the snowiest mountaintops... remote and unforgiving spots to both man and machine. I would say that the models in question are not statistical at their core, although stats were used to tweak precip totals for elevated terrain.
Cristobal colon is extremely remote and rarely visited. #2, Chimborazo, is a pretty rough place up high but it is fairly commonly climbed. Although you won't find a snow gauge there, you would be able to talk to people who have been there if you want to go that route.