Mob Imprisonment Tool not working on llamas

[Shioku1337]

It's pretty simple. I'm trying to use the Mob Imprisonment Tool on llams to easily move them from one place to another and it isn't working.
I mount it by right-clicking and I open the inventory by shift-right-clicking.

To Reproduce
Steps to reproduce the behavior:

1. Take mob imprisonment tool
2. Click on llama

Expected behavior
Llama gets captured as any other mob.