Playing on a modded 1.19.2 server. One of my players tried to turn into a wisp from the Whisperwood mod and was immediately kicked from the server. They are unable to rejoin, with their entire game crashing when attempted. I'm not asking to make the mods compatible or anything, just guidance on having my player be able to join the server again!

The game crashed whilst unexpected error
Error: java.lang.NullPointerException: Cannot assign field "field_3447" because "model" is null
Exit Code: -1

https://hastebin.com/share/cegeropusu.yaml

Here is the paste converted to a file, as pastes on Hastebin expire after at most 7 days:
hastebin-1701142518699.txt

Try editing the player-data with a tool as this one: https://irath96.github.io/webNBT/
You'll have to delete the compound "CurrentIdentity" for your player.