I know I was having fun and posted the xray of the kiwi bird before...
But the only real way it would work was if the Gith conception to egg-birth time was relatively short, and if the eggs were soft shelled and stretched, which would allow for both the egg to make it through the pelvis, and the infant to grow inside and eventually reach a larger size.
It's the same issue with the yuan-ti, who also lay eggs, but they are snake-people and most likely lay soft-shelled eggs like snakes.
