It sounds to me like your chickens are just being - Chickens. You've done what you can for the moment, and now you just need to give them some time to get to know each other. After they've been able to see each other for a week or so, you can give them some supervised together time. That way you can intervene if things get out of hand. New introductions can be rocky for chickens, but if you give them enough time, they'll work it out. Good luck!