Can't see how Itachi would lose.
-Itachi can Karasu Bunshin feint an attack from Sandaime. Crows scatter and can cast Genjutsu that's nigh unavoidable with or without intel, given it will come as a surprise.
-If and when the Raikage is under Genjutsu, his shroud will go away and his durability will be weakened to the point where one can argue that Totsuka could pierce less durable areas of his body ie his neck.
-Itachi's Amateratsu can in fact burn the Raikage. Sure, it will take time, but the Raikage won't just run around like nothing was on him. It'll also make his fighting style sloppy and his decisions less wise.
-Itachi would instantly win with Tsuikyomi being cast. He can use Tsukiyomi as a follow-up to a previously cast Crow Genjutsu, or simply achieve it by itself. No reason to believe Raikage can fight someone by looking at their feet alone, only very few like Gai can do that.