when I grab the ped and walk to the back door to my car the menu at the top left pops up to place in the back and I hit enter, he does the animation to open the door then steps away. the arrested ped then walks to the door and just stands there. I then get the message at the top left that says I can either close the door or leave it open
its the same for all the vehicles I try, the cuffed person has gotten into the driver seat. I have not tried the front passenger and that isn't a realistic option