Can anyone explain how the talisman mechanics work?

I'm specifically looking for help on quick-killing the Report 4 wolf boss.

In the WR, the player is able to quickly react to freeze the wolf in the perfect position, but I can't seem to get my talisman to trigger that quickly. The amount of time I spend in the start-up animation seems highly variable.

I doubt it's random, so I'm just wondering if there's some other kind of input I need to get it to trigger quickly.

Thank you!

P.S. I'm learning this game for a mystery speedrun event this week, so if any happens to have a speedy answer, that'd be amazingly helpful.