I am not going to say its impossible as DMT surely can give open eyed halucination up the wazzoo when combined with a MAOI, but it seems to work on a diffirent part of the visual cortex, I am convinced we have the part of the visual cortex that "sees" ordinary stuff via our optical nerves and another section that we use as a kind of internal eye, the one you can use to recall your mother's face, or what your house keys look like with.
Opening and closeing your eyes while looking at the face of a friend after takeing a good hit of DMT, will show you that those "two parts" of the visual cortex can work together like HUD overlay, with one streaming hyperspace data and the other data based on the world we experience when limited to seratonin as neurochemical. This is my opinion only and I'm sure is in direct opposiiton to the scientific viewpoint, on the other hand I bet none of the scientists ever realy played with the sipce until it revealed its true nature.
In all honesty I'd be much more worried about what it can show you than HPPD. You can forget the stuff you saw, but its very hard to UNKNOW shit you shouldn't know.