This has never been demonstrated it is a myth perpetuated by past speculation.

Acetylcholine has more to do with dreaming and sleep then dmt. There is no direct evidence for much involvement at all for dmt and dreaming. As far as I know.

You should seriously consider lowering doses of your medication and getting to get some sleep. Taking "legal speed" all day and not sleeping can cause health problems it can also lead to amphetamine psychosis if overused. Combining sleep deprivation with amphetamines and dmt is in my opinion a very bad idea.