You said you suspected the texture of the meat, have you tried feeding partially frozen? Some dogs like it better that way, I think. (It's also easier to handle some meats for portioning when they're partially frozen, just a quick FYI
) Otherwise, have you tried to "hunger" him into it? Going a day or so without food won't kill him, but might make the raw look pretty good.
If you're starting with chicken, try a different protein. Chicken is usually cheap and easy to find, which is why a lot of us start out with it. BUT, chicken is also bland, and may not appeal to a dog with a gourmet palate.
If you want to keep trying with the chicken, try making a few slices into the meat, this is apparently more appetizing to many dogs. (Or so I hear, my dogs will eat basically anything you toss in front of her
Another solution I've read about is to ever so slightly sear the meat, and gradually sear less of it as your guy gets used to the idea.