As RatRipper suggests, after all the fine legal arguments, there are just too many violations of fundamental principles at stake for Henderson.
If the writ is denied, the violation of those principles will be reviewed by this court's elders. The issue for Henderson will be whether he can craft a plausible legal argument that protects Sullivans yet honors those principles; an easy question for most of us.
If you mean reviewed by the full DC Circuit, Flynn is screwed. That court is what the Ninth Circus used to be.
Henderson is a she, and it was clear from her questioning that she is Harriet Miers. Not a rocket scientist, if you catch my drift. She's not in the same neighborhood of the vacinity of thinking about "fundamental principles."