Theoretically if a fighter pilot went rogue, what's the procedure to deal with it?

Generally I see the answer "it can't happen", which I agree with--the chances are incredibly slim, but I'm wondering if there is any actual situational procedure written up regarding IF it did happen.

I know getting off the ground without the proper clearance procedures would be a hard sell, but let's say there's stealth jets already in the air training with live ammo and one of them unexpectedly breaks off from the assigned airspace. Doesn't respond to comms. Guy has never shown any weird behavioral signs before so no one expected it. Would they send the other jets in the exercise to shoot him down if he doesn't communicate his intention, knowing he has live ammo? If he manages to get far enough away and out of detection, what's the plan (especially if they notice he starts heading in suspect directions like high density cities or important landmarks?)

Sorry if this is the wrong sub for this. I know the question itself is highly speculative, please bear with me lol.