Eviatar on the DRB process in Afghanistan

In a short piece published at Politico on Monday, Daphne Eviatar (Human Rights First) made a rather bold claim concerning the Detention Review Board process in Afghanistan:

Under international law, a detainee in the Afghan armed conflict has the right to challenge the grounds for his detention to an impartial body with authority to enter final decisions on continued detention or release. The Detainee Review Board process does not meet that standard. To comply with minimum international standards of due process, the U.S. government should provide detainees with lawyers trained to challenge the government’s evidence.

That's certainly not an accurate statement of international humanitarian law (IHL).  Is the unspoken premise that the detention process instead is governed by international human rights law, either becaue IHL somehow does not apply (notwithstanding the reference in the first sentence to the "Afghanistan armed conflict") or because IHRL in any event controls? I'm guessing she has in mind the latter view (perhaps on the theory that IHL in the NIAC setting is relatively sparse) but am not sure.  In any event, I'll pass this link along to her and will post any further thoughts she may be willing to share on this question.