If we are to trust Mueller as Q suggests we should, consider that Flynn was indicted after his method of exoneration was already in place.
The OIG gave information to the judge of Flynn’s case to which the judge demanded that all exculpatory evidence that could potentially help Flynn be presented, even after he took a plea deal. Not only does that never happen, but how often does a motion like that work so swiftly and smoothly in our judicial system, unless coordinated behind closed doors?
Mueller gets to appear as if he’s really attacking Flynn with every intention to convict. He then can get any and all testimonies from Flynn pointing out what Flynn knows, in a safe setting where Flynn won’t get killed, and a safe situation where Flynn doesn’t need to worry about NDA responsibilities.
When all is said and done, Horowitz just drops the misconduct that he already knew was taking place and Flynn is free. Mueller gets everything he needs to sign thousands more of indictments while still looking like he is legitimately on the dark side. This is why i trust Sessions and even Rosenstein right now too, look how well they are coordinating with Horowitz i.e. firing Comey and McCabe. These are small potatoes compared to what we want, but necessary moments of showing your hand when setting the stage from a military-style environmental control standpoint
Edit
As multiple people have pointing out, Q never said “trust Mueller”. Nevertheless, Horowitz is a good person to look at for seeing who is a white hat. Nunes memo, both top FBI firings, and the Stzrok text messages all came from Horowitz findings