Hi Jan,
I've been off AA for awhile (life gets hectic and chaotic at times) and just catching up on your thread. Luka is a handsome boy and he is very lucky to have you in his life, and you are lucky to have him in yours.
I'm so glad you rejected the sanctuary idea and went with a bigger cage instead. I truly believe he would be happier with you and the Sennie's instead of a Sanctuary where he might feel the odd man out. Zon's need big cages, the bigger the better. What kind of toys do you have in his cage? My YNA loves soft wood toys that he can whittle down to toothpicks. My hubby doesn't understand how seeing my Max destroy a $30.00 or more toy in just a matter of days makes me so happy. He thinks it's a waste of $, I think it's the best thing ever. If you haven't given your Luka soft wood toys to destroy, I highly recommend it. My flock also enjoys foraging toys....this is how they get their limited amount of seed they love. I make them work for it. Max also enjoys his showers, he would be happy with me holding the garden water wand over him 24/7/365. I try to give him a good soaking at least once a week, and I mist him daily to keep the dust and dander to a minimum and to also keep his feather's in good condition. I also found that when he is being a hormonal, grumpy butt, a shower or misting changes his mood immediately.
To give you some encouragement, I want to tell you a little bit about my Blue Crown Conure Larry. I got Larry Bird in 1993, he had 7 homes in 8 years. I was his 9th home!!!! He was for sure neglected, and I believe abused as well. He was afraid of hands, he was cage bound and he was terrified of everything. I was told he was a mini macaw, which he isn't. As soon as I saw him, I KNEW he needed me. I tried working with him, but he would huddle in the corner on the bottom of his cage and just shake. It broke my heart. Walking by his cage I would have to keep my hands behind my back. He'd scream and shake and visciously bite when I would clean his cage or change out his food and water. I didn't know what to do to help him. He was terrified of toys, he'd just sit on his high perch and do absolutely nothing. I promised him that no matter what, he wasn't going anywhere. He had nothing to fear from me. I would never, ever hurt him, no matter how much he tore me up when servicing his cage. I put a perch on the inside of his cage door, so that when the door was open, the perch was actually on the outside of his cage. When I was home, I would keep his cage door open, giving him the choice to come out or not. I decided to accept him just the way he was. He was going to have stability, healthy food and he wasn't going to have to worry about getting hit, or having his caged banged on or having pot smoke blown in his face, and he sure as hell would never eat pot seeds again (one of his homes was a frat house, a real party house).
Jump to 2016. Larry is still afraid of hands. He no longer bites when I service his cage. 9 out of 10 times when his cage door is open, he will come onto his outside perch and wait for me to offer my forearm (never my hand) which he will step up on. He will allow me to carry him over to his play stand. He likes riding on my shoulder and whispering in my ear and preening my hair. He does not like being petted or getting scritches, but he will allow me to help get rid of the pin feathers on his head, in short preening sessions. He occasionally plays with toys and actually destroys some wood toys. He will never be a cuddlebug, he will probably never ask for head scritches. That's okay with me. He is who he is and I love him to pieces.
Just accept Luka the way he is. Offer him toys, offer to play with him, but let him do everything at his pace. Love him for who he is. YOU be his sanctuary and let him know he is loved and safe. Wishing you two the best.