The whole investigation, as any investigation, is to answer the question "Is there sufficient evidence to charge the person with this crime" the answer to that question will be yes or no. In this case it is No. It's not, is this person innocent, because you can't know what evidence you lack, only what you have.
It appears, by such a statement, that there is evidence that supports obstruction. That is not uncommon with any investigation or any hypothesis in dispute. But that evidence is insufficient to proceed legally. That is the take away, this is done, there is nothing more to do unless we want to continue the narrative and speculation not with the promise of evidence as before, but with insufficient evidence. An investigation, such as this, is not capable of declaring innocence, only legal justification for prosecution.