No he used 2 Tsukiyomi's in part 1. And an Amaterasu. And didn't even show signs of fatigue until after he used Amaterasu on Jiraiyas toad mouth trap and that only resulted to deactivating the Sharingan. But when he fought Sasuke was when his sickness started to REALLY get to him, and was already on the verge of death and blindness. And he still outlasted Sasuke even though he was sick and used Tsukiyomi and multiple Amaterasu's and maintained Susano'o for like 6 minutes. And even reactivated it. Sasuke chakra was completley GONE even curse mark, while ITachi had a FULL complete version Susano'o. So you can't say Itachi has low chakra, cuz Sasuke had plenty, and ITachi outlasted him. SO im pretty sure ITachi can spam multiple Amaterasu's on the paths. And if he AMaterasu'es the path that revives the other paths, then no paths would be revived.
But i do not see any pains dodging Amaterasu, it's just too fast, basically instantaneous definatly faster than a rasen-shuriken. Preta path cannot Absorb an Amaterasu that is directed to him. It will instantly catch him on fire. Even if he knew it was coming, it's not like the fire is gonna be placed in front of his hands so that he "can' absorb it, it's gonna catch him right on his body, or wherever ITachi wants, like his head or something.