Red Eye (2005) - 3 questions

Question: This just interests me, but how on earth did Jackson manage to get a ticket right next to Lisa on the plane so quickly, considering that Keefe changed his plans at the last minute, and they didn't know Lisa's grandma was going to die, and she'd be taking the last plane back to Florida?

Answer: These are very tech-savvy terrorists. Not only would they be watching Keefe, but also Lisa, who is integral to their assassination plot. The assassins would have been monitoring their every move, intercepting cell phone calls, hacking into the hotel's and the airline's computers, and so on. It is unknown how Jackson got a seat right next to Lisa, but as it's a late-night flight, there would likely be fewer passengers and he could have managed to be seated next to her or somehow got the airline to switch him with another passenger.

Question: Is it actually revealed why Jackson wants Keefe dead? Did I miss something?

Answer: It's a political assassination plot. Jackson is an operative working for the terrorist organization that wants to kill Keefe because he is the Deputy Secretary of Homeland Security.

Question: I don't understand parts of the scene where Lisa runs over the hit man. The hit man is just standing outside the door for some reason. After Lisa runs over him she runs inside the house and her father said he called the police already, why did he call them? The hit man was just standing outside waiting for the call, her father didn't know what was going on. Did he call the police because she drove into his house, even though there had only been a few seconds in between scenes?

Answer: Yes he called because she hit the guy and ran into his house. When 911 calls back they say that they had a call about somone being hit in front of the house and asks if they still need the police.