It's not that easy for us. We don't know who's lying between you two. Since no role is unique in this game. Claiming strong roles is easy. And Lhulu literally made this 1 v 1 exchange. So if you're actually the Vet, then he couldn't have gotten guilty on you.
Also since you're a Veteran, going on Alert to prove yourself won't help. Like Odd said, the Coven leader can control someone to you and kill them while you're on alert. We need an investigator to clear you.
How do you know Don was never attacked? You think Zem wouldn't have let TACy use his double action to attack?