The achievement “To All the Squirrels Burrowed Beneath” (achieve ID 18361) requires targeting an Aimless Snail (ID 201875). In order to see an Aimless Snail, you need to be on the daily “The Slowest Fan Club” (quest ID 74514).
If you are max reputation with the Glimmerogg Racer faction Briggul will not offer you the daily quest, therefore you can never see the Aimless Snail.