There are many options. Individual litigants can ignore NLRB rulings; and, following the administration's lead, might as well feel free to ignore court rulings as well.
-- But this really is getting serious now. --
I enjoy a meaty constitutional crisis.
That said, I don't see much harm in the NLRB acting as though this decision will be reversed. If the case was heard in a different Circuit, the result would have been different - so, looking forward, current cases may end up with appellate courts holding that the appointments were constitutional.
Fascinating that there really isn't a rule of law, and that the constitution means whatever the most powerful bully says it means. SCOTUS, the ultimate bully, will speak up in due course.
“That said, I don’t see much harm in the NLRB acting as though this decision will be reversed.”
One private dollar wasted in the process is enough harm for me.