Just contesting the notion that Satanism could be truthfully argued to be "not a religion" and thus have no standing in any religious argument. Outside of that, I've not read up on this particular case, so I don't really have an opinion on it at the moment.
Many flavors of satanism explicitly reject theism and have no doctrine or organization. So, not a religion. Sort of like trying to claim one's "freedom of ruben sandwiches" when one has no rye, corned beef, saur kraut, swiss, or dressing.
OTOH, such falls under freedom of conscience, which most have considered to fall under the first amendment.
Not sure how there is any nexus between the HL case, the first amendment, and abortion. But, like fistful, I think associating satanism and abortion has its upsides.