Defossilize doesn't cast if you control 3 creatures

Edgar

Defossilize didn't cast while I had a creature in my graveyard, until I had less than 3 creatures.

Setup:

Tyvar, Jubilant Brawler (Loyalty abilties were not used)

Case of the Gorgon's Kiss
Rush of Dread
Vraska's Fall
Festering Gulch
Kraul Whipcracker
Bramble Familiar
Monstrous War-Leech
Daggerfang Duo
Chalk Outline
Defossilize

The attached Screenshots are in Eternal? Training Grounds (I don't know what you call the blue game modes, where you can use any card in your collection). But this also happens in Standard Training Grounds.

The revival will not work even if it would hit a card that you already control. It seems like you must have 2 or less creatures.