Blockus messes up block data if you join a server that runs off a proxy

Recreation:
Download Fabric 1.20.1
Download Blockus 2.7.4
Connect to our server.
mc.oresfallorigins.com

See the bugged out mess

the issue has been found in multiple mods. (im network engineer of the server)

Basically the mod breaks blocks on vanilla servers.
This bug can be found in multiple mods like: traverse, dawn api, cinderscapes, blockus, terrestria