I have administered DMT to many individuals in a very similar fashion. Even with proper vaping technique, I have noticed massive variation in tolerance and particulars of effect. The middle of the bell curve seems to be around 40mg for a full breakthrough, but I've seen people break through on as little as 20mg and not break through on as much as 200mg. The particulars of effect are very unpredictable. Even the same person doing the same dose on two different occasions can yield wildly different effects.