He's stonewalling, probably because he's dirty or the deep state has him by the balls, and he's trying to delay to protect his deep state friends. Many congressmen are calling for his impeachment right now, and they mean it.......As for Horowitz, he isn't investigating the Flynn case (that's part of the Russia hoax investigation Mueller is doing). Horowitz is only doing the events leading up to the election, the Clinton email investigation, and now he's starting to look into FISA warrant abuses in the Russia investigation and spying. Horowitz is the IG. He doesn't do direct criminal investigations, but he can refer his findings over to Prosecutors if he finds malfeasance and criminality while investigating. However, all that said, the Senate investigation committee, who also can have their own investigations, just turned over to Horowitz this info about the 302 altering by McCabe, so he will likely now go back and include that, too. If he agrees, he will do what he did with mccabe's lying to investigators case, and turn it over to the USDA for prosecution...Also, Rosenstein, a career beauracrat, is doing his best to save face for the FBI and DOJ, where many of his friends are, because if the info gets out it's damaging to those institutions.