It turns out ALL the WhM weapons have Piety this patch.

The Tome cane, Crafted cane, Savage Cane and Ruby Weapon Cane are all Piety. Not only that, Piety is the larger of the two stats in all cases.

I almost wonder if it's an intentional small nerf to WhM dps. Piety is a 100% dead stat for WhM in anything besides Savage progression and Ultimate. It does nothing unless the content demands you push your healing to the limit.