Hello, anon! You're correct: Tyrunt and Amaura, like the other fossil 'mons in Route, are not available in the wild. We made them available as a part of the Swarm September event (much as we had a similar fossil event a few years back), but for now they've returned to their former state of near-extinction. People who snagged them as a part of the event are welcome to breed them, though, so it's always possible to get hold of one that way!

As for Snover, that was an unintentional oversight. We'll get on that right away!