Interesting, it is chicken ham, never heard of this before. Of course, I have no compunction about eating ham ham and not chicken ham. It is similar in function and process to the teriyaki chicken breast roast that my family has made for a long time.
We cure chicken thigh or breast meat, boneless, in a traditional teriyaki marinade for 24 to 48 hours. This pulls moisture out of the meat like a brine and causes the chicken to cure and take on the soy/sugar/salt flavor components and gives the meat a dark red appearance. When smoked properly, it takes on a deep pink color and forms a skin on the surface. It is delicious and done correctly, moist, salty, sweet very much like a ham texture.