I agree, chicken is an odd texture and flavour to start with. The first time i gave it - i gave it 'neat' and got the same reaction. After that I always added in some veg especially ones that were a favourite. I gradually increased the amount of chicken compared with veg in the mix.
However, the best way many of us find to introduce chicken is to cook it WITH the vegetables as a mini casserole.
The first time - I cooked it with a couple of veg that I had introduced. Once he was fine with the chicken, I used this basic idea to then introduce other veg that I hadn't done as they are'nt ones you'd give on thier own - onion, peppers, mushroom etc.
I also used the same principle to introducing other meats / fish. Adding these new meats to known familiar combinations of veg.
HTH
Alex