First the store plants in moss likely have rotten roots and are unable to take in much water. That will require different care than just underwatered plants. Get them out of the moss as soon as you can to prevent further damage. They are better off without a pot in the air than rotting in the moss. If their roots are rotting, they need to have good humidity and the roots need to dry out between waterings, like all Phals.
For your others, I would give them a good soak, so they take up what they can, then let them almost dry out and do it again. It won't help them to over water and rot their roots, they have already adjusted to your care. You can water them more often (most likely), soak them when you do, but be sure they aren't wet the next time you water. That will kill the roots.
Your Shelob will love humidity, air movement and possibly watering more often. Watch the media, don't keep it "wet", but water it just before it dries out. They are susceptible to fungal infection on the leaves from lack of air movement. Watch for spots and spray with a fungicide at the first sign.