More like the Mongols would win because of silk. Survivability of wounds is one of the most important factors.
Also the Mongols were an ‘Iron Age +’ people, the American Indian - Comanche in this case were a ‘Stone Age’ people.
Note I am assuming neither aside had access to firearms. Also as far as I know no North American tribe smelted metal for weapons.
So Mongols with a easy win.