I just tried this. Hovering over the pet equip in the cash shop inventory will show the item as clean, but when you take it out it will show the correct stats in the player inventory. I was unable to make the pet equips clean again. Can you confirm that this is the case for the items you have, and if not, what are the names of the equips you are using?
Can confirm, my hp equips are still scrolled after taking them back out of cash shop. Just a visual bug then.