1.21.4->1.20.6 - Swift Sneak III triggers Grim AC when taking damage

[Kyuunex]

General Information

https://dump.viaversion.com/7e806c5328105a502deefd1e8416ff25d369f22007d92b3fcf29a67ced4c812a

Bug Description

Server is 1.20.6
Client is 1.21.4
Server has Grim Anti-cheat installed. Grim Anti-cheat simulates player movement to check for irregularities.

Swift Sneak III works fine until you take damage (tested Skeleton shooting me)
After that, Swift Sneak III movement is so that it triggers Grim AC and causes rubber-banding.
Relogging fixes the issue, until you get hit again.

Steps to Reproduce

1. Open 1.21.4 client with ViaFabricPlus installed
2. Join a 1.20.6 server that has Grim Anti-cheat installed.
3. Have leggings with Swift Sneak III enchantment equipped
4. Take damage (tested Skeleton shooting me)
5. Attempt to Sneak
6. You will be rubber-banding

Expected Behavior

Swift Sneak III should work fine, even after taking damage.