OP can ask any question he wants. He won't get answers to anything other than whether he may be rebooked. That will depend on his fare conditions and his willingness to pay the fees if any.

Both federal and state law fugitives, violent & non-violent, are returned to their "home" jurisdiction by both federal and state law enforcement and those agents & officers are armed as they ordinarily would be.

There are hundreds of these transports every day. I am very surprised that OP, if he is a regular flier, has not routinely encountered this situation on UA and other carriers. Ordinarily the prisoner & escorts would have been pre-boarded, most often from the ramp. But, there is no requirement and certainly no particular issue in the way this was handled.