There is a piece coming up in that set called the Titan Skull Cave, It should fit in perfectly. maybe put it in the opposite corner to the dragons skull?
Ohhh the godbeast tracks are a sweet idea, the thing that managed to kill this awesome beast!
Wait I can do one of those, its an older set but we made one back in the day: https://www.printablescenery.com/product/sand-worms/
Oh I agree wholeheartedly, its my favourite set from the latest releases: https://www.printablescenery.com/product/dragon-graveyard/