My answer is : not sure.
The fact that simon's turned blue is very much shows the presense of the secondary amine. That coupled with your marquis reaction you can be almost certain you have MDMA.
The fact that it turned blue without the buffer being added would mean there is a another chemical present that is taking the place of the buffer, which is making simon's react straight away. This is not a common reaction but it can happen. I have seen it happen with methamphetamine pills rather than MDMA pills, and I have always assumed there is a chem that is present that is a bye product of a poor synth.
What can we say about this pill then?
Well, it certaintly contains MDMA, but it also contains some other substance. What that substance (or substances? considering the buffer caused a reaction as well) is I'm not sure. It certainly contains more than straight MDMA + normal binder + normal filler.
My advice: If you are uncertain about a pill, then don't consumed it.