I've had similar issues with my girls. When I first started letting them out of their coop to free range, I'd find them roosting in a tree next to the coop at dusk rather than going in their coop. I tried locking them in for a week, but they still intermittently used the tree. I would knock them out of the tree with a broom handle to put them in the coop. I started giving them dried meal worms as a treat to entice them in, which would work as a lure, but then they'd get in there and wait before I'd show up, and then come back out (I would arrive just as they were coming back out). Now, if I'm on time, they will go in and I lock them up, but if I'm late, they're in the tree. I tell them "chickie, chickie, chickie" and put the mealworms in the coop, and they'll jump down and go inside. Two of my new girls will go in no problem but the original ones still insist on starting in the tree and then will come down when I call them, and go inside. Sometimes they get mealworms and other times not. If it is too dark when I come, then they won't come down and I have to physically grab the legs of the ones I can reach. Thankfully, we don't seem to have any raccoons or opossums that would go up in the tree to get them, because sometimes I just have to leave the ones who are too high to grab. Not much of an answer for the OP, but at least the treats will help you get compliance if the don't end up volunteering to go in.