Hmmm this post made me think, how will this undo Edo. If going by your pretake on it, it can only loop to the events Itachi witnessed with Kabuto. Submission? And if that's the case, I'm very disappointed now haha
I pointed the same thing out on another thread. "Forcing" Kabuto to release Edo Tensei of his own accord is a pretty stupid strategy on Itachi's part. The only reason why Kabuto is still alive is because Itachi can't kill Kabuto before he releases Edo Tensei. And I'm sure Kabuto is eventually gonna realize(if he hasn't already) that releasing Edo Tensei will mean that the Uchiha bros aren't gonna be gentle anymore. Basically, ending Edo will mean the end for Kabuto. So, why would he willingly give up that kind of leverage just to get out of a loop.
He can always do it at a later time. Like after Madara won or something. Its not like he's suffering or anything. I'm sure that Kabuto is still aware of whats going on in Madara's battle. And I'm also sure that his plans are not being compromised by being momentarily stuck in a genjutsu-loop.
[edit] Infact, I'm bold enough to say that Itachi's actually the one thats stuck in the Izanami-loop
Why? Well for starters, Itachi cant kill Kabuto. Which means that Itachi cant end the loop by killing Kabuto. And secondly, it seems that the loop will only end when Kabuto ends Edo Tensei. Which means that although Kabuto's destiny might be set in stone, the timing of his destiny still seems to be in his own hands. Which means that only Kabuto gets to decide when Izanami should end. And Itachi is stuck with Kabuto until Kabuto makes his move.