Hello and Welcome to Talk Parrots, 3 months is not a very long time to establish trust with new birds. Its great you have bonded with the hen and she is interested with you already, now you will have to work with the cock bird individually and often to get him more use to you. This may take weeks .... or months. He needs to learn and trust you and it all takes time.
Try offering him white sunflower seeds as a treat, offer them to him many times during the day, if he responds and accepts the treat praise him with a happy excited voice. He will pick up on the excitement in your voice and see you are pleased which will excite him in return. In order for him to hear your happy voice and see the treats come with it he will respond more to you.
It's a slow process but as I said you haven't had the birds very long so just work slowly day to day and hopefully you will see results. As for being in the cage all day? Some birds like to be in their safe home and some don't ... tiels are foragers and love to run around the floor and investigate and get into mischief and they obviously feel happy and secure outside their cage so don't worry much about this.
I often read comments and questions from most bird owners saying they can't get their birds to come out of their cage EVER ... you have luckily managed to have happy content birds who don't mind their freedom. A way to keep them in their cage more often is to offer fresh foods in the cage daily, a dish or bowl of water they can bath in and you can re-arrange the cage with new and interesting toys/ladders/perches and objects they will be happy to play and sit on while in their home.
