I think i figured it out! Ive been playing around with the slight roll back the train has when it is let go to hook onto the catch car.
I started with sloped track. Then I used a tiny lift track with like a .001 acceleration so the train can go forward but stops when falling back on it (like the catch car!). Then after that i have a brake section that i calibrated so that it has 0 accell on the transport, launch of 1.7, then make it so the train has a complete stop slowly right as the last car clears the lift behind it, then for some reason it just falls backwards and stops at the lift, where it stays as many seconds as you make it. The only problem is that it doesnt ever stop completely BEFORE falling back onto the "catch car". But if it slowly decelerates it is still pretty convincing.