I think I know what causes that bug. I'll try to have this fixed tomorrow, thank you!
The Snail spawns in the river crossing, but it only has a 5% chance to spawn each day, with an extra +1% for every point of Luck you have. (Having the Bad Luck Trait cancels this extra bonus!)
The Snail is not actually new, it has been there ever since Garnet Weald first came out, Aria just brings that fact to attention :)