I do not have any experience with wild caught parrots of either aviary type or companion type of species, but I do know that unless you hang out in the same room as he is in and talk to him frequently even if it is at a distance that he will never get used to you enough to come to trust you.
The closest that I have to a wild caught bird is an ex-breeder bird, which are very often impossible to get to trust a human due to their past treatment by humans. I talk to him all of the time and he is in the same room as my other birds and myself. He gets to watch me as I interact with the other birds and as I go through my daily activities and I drop the occasional treat for him in his food dish when I pass by. I do not reach into his cage or put any pressure of any kind on him. When he starts to move towards me in his cage in anticipation of me coming closer then I will know that it is time to start working on hand taming him, but not until he shows me that he is ready for it.
I know that you want to interact with him and to build a relationship with him, but this is something that must be done at his pace and if you watch him and learn from him, then you will be able to see when, if ever, he is ready for the next step in that direction. These birds live for a very long time, so don't get caught up in worrying about how long it may take or start pushing him to accept you as that will only keep him from accepting you.
I have a bird that was mistreated for 14 years and although she is a companion species and captive bred and raised it took her over a year before she could begin to trust us at all and it was still another year before she would even come to the outside of her cage set up with both toys and perches for her. It has taken three, almost four years for her to accept being out of her cage and to perching on her human's arm for more than five minutes.
Other than what I have suggested already, the only thing that I can recommend is more patience and consistency and to allow the bird to set the pace.