Tbh that was more PIS than an actual feat, you can't really make sense of it at all.
His focus is on Dooku, he immediately turns and deflects two simultaneous bolts shot at him that came at him when he wasn't even having his attention on Jango.
There's a delay for Jango's 3rd shot(a smidge longer than his first 2 simultaneous shots) and Trebor gets hit because.....why? There's literally no reason for him to have been shot, when he had previously deflected 2 bolts when he wasn't even paying attention to Jango. The delay on Jango's 3rd shot should have been easier to deflect than the first 2.
This is just using the movie alone, looking into the Legends behind Trebor, his death makes even less sense.