You’re right and wrong.
In the general sense who invented a hoax of a charge does not matter.
On the other hand, if the CIA, Brennen et al had never had any hand at all in the formation or selling of the Steele dosier and it was entirely a Billary, Inc., Fusion GPS & DNC instigated and contracted matter, the only legal concerns vis a vis the Obama administration’s use of that dosier would be how it got shopped to, accepted in, and used by FBI/DOJ aparatchiks to frame the collusion hoax on Trump.
What the Brennen part shows is that the CIA is also a suspect operation, which has information tentacles and connections far deeper than FBI/DOJ, BECAUSE of their intelligence capabilities and abuse of same. I would not be surprised if that community has other tricks they are waiting to launch in 2020; as they can be both the manufacturers of “intelligence” and the official authority on the veracity of it. Yes, with a lot of digging we can uncover the lies, as we did with Plame and her husband, but it means another giant domestic “intelligence” war that will have to be fought.
I have no doubt that the CIA & Breenen at all were trying to bring down the Trump administration, just as the intelligence networks used Plame and her husband to try and bring down the GWBush administration.
My point is that dossier is fully manufactured. It is more like a pulp fiction than anything else. Why blame the author and does his identity really matter? Who ordered and used it is important.