When I use a command saying: /replaceitem entity @e[type=zombie] slot.weapon.offhand 1 totem, it stabs the zombie. 

What I thought would happen...

The zombies would look humanoid like drowned, and hold a totem.

What happened...

The zombies DID look humanoid but they were stabbed in the neck by the totem

How to see this...

Do the command mentioned above.