Baby zombified piglin riding on chicken is picked up by a minecart. Then sometimes the minecart gets stuck randomly when going around the corner., No entity collisions.

Video: https://youtu.be/W56aRXIee8E

Sample WDL attached, verified in vanilla 1.20.5 Minecart goes in a cycle, picks up jocket, goes around 2 corners, unloads the passenger and gets broken. Command blocks kill jockey and spawn a new one.

I'd say the problem happens about 1 in 10 or 1 in 20 times. So you may need to run the setup for a bit but eventually it will happen.