Syncing animations with Geckolib

I'm trying to sync the damage to a certain point of my attack animation. I've tried various solutions but couldn't find any that works perfectly.

I've tried C.Jiangqu's tutorial but could never figure out where that "sqrt" block even is even though I installed both plugins
https://mcreator.net/forum/104312/tutorial-solving-mismatch-between-geckolib-entity-attack-animation-and-attack-timing

I've also tried bo_bo's procedure but even when I set the attack to 0, it still "damages" (causes the target entity to be red) the entity
https://mcreator.net/forum/108498/gecklib-attack-animation-not-syncing-damage?page=2

I've also tried Procedure Guru's video tutorial but got stuck on where he found "Get Local Xpar"