Sam
Did you exchange a walk on part in the war for a lead role in a cage?
So Hollowed Grounders weren't allowed in the Greatwood.
Sam normally wanted very badly to follow rules and minimise trouble, but he needed a hanging snake. So he would go into the Greatwood, briefly, invisible. Just in and out to grab a snake and leave - no harm would be done and he would be out holding a snake before he knew it.
He hoped.
Walking over the border from the Outskirts, staying close to the ground and slow, he looked up to the tree branches for a snake hanging down. They were relatively common creatures so he hoped to be able to find one within fifteen minutes; eventually he saw the mottled scales and bright curious eyes ahead of him and reached out to take the snake, gritting his teeth. Did The Voice want the snake alive?