All of this is permissible for play within the D&D Adventurers League.
The Snout of Omgar is a geographical region described briefly in Tomb of Annihilation.
Not much is revealed about the location or its inhabitants in that adventure, however. The Tortle Package is written for Dungeon Masters who want to know more about the Snout of Omgar.
Discover the other books benefiting Extra Life:
- Infernal Machine Rebuild
- Mordenkainen's Fiendish Folio Vol 1
- Locathah Rising
- One Grung Above
- Lost Laboratory of Kwalish
This purchase unlocks the entire contents of the book version for use with D&D Beyond, including the content in digital format in the game compendium and access options from the book in the searchable listings, character builder, and digital sheet.
Proceeds from this product support ExtraLife. You can head to the D&D page on Extra Life to find out more.