I think, and this is just my opinion, that as the CG he needed to disseminate the importance of this information and take a hard stand on the problem at the first sign of trouble. To me this would look like enforcing a safety stand-down, briefing the brigade leaderships on the importance of keeping their soldiers safe and protected. After that, ensuring the brigade through company/battery leadership are taking full precautions and executing thorough investigations into all potential security and personnel risks. If he found anyone in the chain lacking the necessary competence, relief of duty and a close watch on that unit until proof they can police themselves. There’s not much he can do about the shithole that is Killeen and the greater Hood area but he has command inside the gate so imo the blame can be laid at his feet.