Incompatibility with Vanillin mod on NeoForge 1.21.1

[mpustovoi]

Describe the bug
The game crashes when enabling shaders with Vanillin mod installed.

To Reproduce

1. Install the basic components:.
   
2. Launch the game, enter the world and build something out of block entities.

Logs: https://mclo.gs/0aJfp3c.
hs_err.log: https://mclo.gs/xTOYFK6.

Screenshots
If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• MC version: 1.21.1
• Iris version: 1.8.8+1.21.1-neoforge
• IrisFlwCompat version: 2.0.1
• GPU: NVIDIA GeForce GTX 1060 6GB, latest possible drivers.

Additional context
The crash didn't happen on my other modpack instance. The block entities and entities models affected by Vanillin mod optimizations (chests, shulker boxes, bells, minecarts) were just bugged with shaders enabled.
Logs: https://mclo.gs/jDHZK2R.
I wasn't able to track down which particular mod combination doesn't lead to crash, but the minimal setup shouldn't give any crashes.