High amounts of "body dropping" and fake deaths

Artifacts: 5181
What I expected to happen: Client A shoots and kills Client B
What actually happens:
When shooting a player their body drops and they appear to be dead on Client A (shooters) screen, but Client B is still running around and playing with no issues at all. This causes Client A to stop shooting as they assume that Client B is dead and shortly after Bs body drops it appears to just get back up and start shooting instantly

I have seen this issue posted back in 2020 and a few others having issues but I can’t seem to find the route of the problem
Old post: Damage/Death Desync (OneSync)

Clip: Desktop 2022.03.24 - 01.27.58.16.DVR_Trim

No repro, no fix.

The repro provided back in 2020 was fixed, so this is likely unrelated.

Any idea what could be causing it
Only thing I can think of is the CEventNetworkEntityDamage handler we have to display damage numbers, but that handler is removed when joining a lobby where this setting is disabled. Could any interference with that event cause an issue like this across the whole server?