I had never head of that organization, either. I did do a (very brief) check, and it looks like it's less than a year old. Their web site says they're a KKW TKD affiliate, so they're expected to teach the taegeuk and yudanja poomsae. They are, of course, free to teach whatever else they want in addition to those forms. GM Chun was originally a Moo Duk Kwan practitioner, as am I. Chintae is not part of the KKW or MDK curriculum. However, there is a Chintae kata shotokan, and many of the founders of the original Kwan had shotokan training. GM Hwang Kee, the founder of the Moo Duk Kwan was one of the few who did not (there are claims that he trained to the equivalent of green belt, but he denied this). GM Hwang was primarily trained in a branch of Taichi Chuan. GM Chun could, obviously, have learned Chintae from someone and decided to add it to his curriculum, but as I said, it's not a part of the KKW or MDK curriculum.
I suspect you're right in thinking that it's the same form taught in Shotokan. I'd say it's incorrect to describe it as a TKD form, though.