Aloha Ryan, let's try to break it down:
OHA is a part of the state of hawaii government. It was created in the 1978 State of Hawaii Constitutional Convention. It's mandate:
The Office of Hawaiian Affairs shall hold title to all the real and
personal property now or hereafter set aside or conveyed to it which
shall be held in trust for native Hawaiians and Hawaiians."
OHA was created to help redress and protect Native Hawaiians. For younger people like us, it is hard to imagine the situation before the Hawaiian Renaissance in the 1970s. However, it is still part of the State of Hawaii, more so since the Rice vs Cayetano ruling which meant all voters in the state voted, not just native hawaiians. So they are not an independent entity.
I understand they hold land in trust until a native hawaiian governing entity is formed. This is land which was taken from the Kingdom by the Republic of Hawaii illegally, transferred to the US, then to the Territory/State of Hawaii. However, i do not know the legal mechanisms involved to transfer title. I assume if we get to a strong negotiating position, it is possible.
DHHL is part of the State of Hawaii. It was formed in the U.S. Hawaiian Homes Commission Act of 1921. Prince Kuhio was part of creating it. He was part of the 1895 rebellion against the republic of hawaii after overthrow, and did prison time for it. After annexation, he was elected to the US congress as a territorial delegate. He wanted land grants to Hawaiians fee-simple (not leased) and 1/16 blood quantum (not 50%). So he got something for hawaiians from the US but it was watered down a lot. How we change the mandate of DHHL, reform it, or remove it, this is also up for discussion. At the end of the day, they are part the State of Hawaii under US Federal government and are dependent on that process. The act is considered one of the only legal protections for Native Hawaiians having specific rights based on ethnicity in the US system.