I'd check with the local PD about whether it's safe to leave your car at the Lawrence Amtrak station. Even places that seem pretty safe can be risky. For example, I called the Pasco PD before boarding there, and they said "Oh, no problem at all! Unless you have a Honda Civic..." So I left my Civic (LOL) at a friend's house and got him to take us to the station. I guess they are popular to strip.
Hubby's from Kansas, went to KU in Lawrence, has a brother that lives there. He says it's a bad part of town. We got off at Lawrence just once, and sister-in-law said she was nervous just sitting in her car waiting on the train at that hour of the night. I did not notice any cars at all in the lot, just Mary waiting for us, but then, it was winter.