Board Thread:Naruto Discussions/@comment-1018594-20160409062530/@comment-24824859-20161016144456

Thekillman wrote: First off, yamato would've told him about his origins (hard to explain his wood release otherwise) and they would've known there was about a 1-in-60 chance.

Secondly, Danzo used it on himself and nearly lost control, something Sasuke and Karin witnessed and would've relayed to Konoha.

So yea Konoha knows that compatibility is unlikely and that you need powerful lifeforce to balance it (and in Sasuke's case he already received some Hacky cells from Kabuto) 1.) Ok, that makes sense 2.) Danzo had Hashi's DNA for a while and had it in control for the majority of his fight with Sasuke Sasuke didn't receive Hashi's cells from Kabuto. But regardless, I guess they figured it would be too risky integrating Hashi's cells in an individual