I was hoping an ITF member would answer, but I guess not.
The Oh Do Kwan was never a part of the ITF, although many believe that the ITF and Oh Do Kwan were the same thing. They were not. When the ITF was formed in 1966, the Oh Do Kwan Jang was GM HYUN Jong Myung. He was very close to Chung Do Kwan Jang UHM Woon Kyu so GM Hyun kept the Oh Do Kwan with the KTA group, as opposed to the ITF. GM Hyun was also a member of the KTA ad hoc committee that created the Palgwae and Yudanja poomsae from 1967-68, which was important because then the KTA could honestly say that the Chang Hon forms that the Oh Do Kwan was using influenced and were incorporated into the new KTA forms.
...GM HYUN Jong Myung was a very influential Taekwondoin. He was the one who worked out/taught GM HWANG Kee the Chung Do Kwan curriculum when both worked at Seoul Station, he was present during the Taekwondo Naming Committee meeting, served as Oh Do Kwan Jang...He is also a Kukkiwon 9th Dan.