[Crash] when catching a mob on 1.21.1

**Version info**
Minecraft Forge 1.21.1
Portable Mobs: portablemobs-1.2.1-forge-mc1.21

**Steps to reproduce**
Craft a basic capture cage and catch anything? (tested with a zombie villager for the latest.log and a chicken after that)

**Crash report (~/logs/latest.log)** 
[latest.log](https://github.com/user-attachments/files/17311443/latest.log)
