Your assumptions are a little weird. You're assuming this is publicly available software, and that it is an attack program that can circumvent at least some cars systems. Most likely, neither of those is true.

Much more likely is he has the manufacturers interface software on the laptop, and the plug wire to go with it, and he can use that to override the inboard computer. Because nothing else should be able to override it (let us assume that the manufacturer isn't a complete fucking moron, for now).

The working theory is he has a Jeep key, and he's using the laptop to associate the key to the jeep.

Without a working jeep key, you can't bypass the steering lock (it's physical). Even if you can start it, you can't drive it.

Well... steering locks are pretty easy to break, in fact. My guess is, in a jeep if you break the lock, the steering column is still intact. Being a jeep and all. Don't try that on a toyota, it just breaks the column itself. Or a modern MERC where the column isn't even attached to anything besides a sensor.

As someone that likes to play with electronics, let me tell you a few things about modern cars... THEY ARE TERRIFYINGLY EASY TO COMPROMISE. They almost all have various forms of NFC and or WAN. They accept information from the outside over RF. And the "rolling code" shit for car alarms has been compromised since just about the time it came out. You just need to sniff the last transmission, and know the make of the car. There is a rainbow table for most manufacturers already.

I have a raspi that can attack and try and take over in car entertainment systems. As it turns out, most of them are just android tablets. With terrible software. It works rarely, but it's spectacular when it works. Someone is going to make that better some day.