I'm not OCD (or if I am, it's in the most minute of ways), and so while I can't necessarily put myself in their shoes (and I know how different people can be OCD in different ways) I have essentially two scenarios playing out in my head for an OCD person who takes DMT. In one scenario, the mathematical precision, well defined spatial relationships, potential neat and orderliness of hyperspace might call to the OCD person. Perhaps it removes him so far from the real world that he gets momentary relief from his OCD where his typical thought patterns cannot intrude. Perhaps breaking the cycle so to speak is enough to create long-lasting therapeutic benefits.
Then on the other hand, in the other scenario DMT could hit you with the sheer wacky, silliness with nonsensical geometries, and goofy disorder, and I don't know how an OCD person would handle that. Perhaps this scenario could also potentially be therapeutic, but who knows. I'm just freely speculating.
"Science without religion is lame. Religion without science is blind" - Albert Einstein
"The Mighty One appears, the horizon shines. Atum appears on the smell of his censing, the Sunshine- god has risen in the sky, the Mansion of the pyramidion is in joy and all its inmates are assembled, a voice calls out within the shrine, shouting reverberates around the Netherworld." - Egyptian Book of the Dead
"Man fears time, but time fears the Pyramids" - 9th century Arab proverb