You've pointed out some of the problems with the study mentioned here. The biggest problem is that these monkey studies may or may not reflect the human situation, especially so depending on the route of administration. I assume this study was done by i.v. injection. That alone makes it very difficult to draw any conclusions relative to human use of these drugs which is mainly by oral ingestion.
I wonder how it is that some dufus mislabelled the bottles of these two drugs; that kind of thing can get one's DEA controlled substances license pulled, not to mention a whole lot of raised eyebrows among the peer-reviewers of your published work.
I suspect there were no mislabelled bottles.The "study" was a fraud in an attempt to get the "right" results.
Legit pure lab grade MDMA is not a high volume production item and is no doubt closely tracked and handled.I don't believe those who have license to legally manufacture and distribute schedule I substances make these kind of mistakes.