Minecraft 1.20.1 Forge 47.2.0

With JER installed when looking through the list of Mob Drops it crashes. The crash report seems to indicate it might be Dragon Mounts.

crash-2023-09-26_17.42.35-client.txt
latest.log

This happened when I tested it with just JEI, JER and Dragon Mounts as well. Reporting this on both mods as I do not know which end it can be corrected from.