I have a fair bit of doubt that this individual would have received their DTK prior to WWDC. Let’s assume you are correct and there was DTKs in the wild. These individuals would have a higher level of NDA than WWDC DTK release kits, right? So then someone stated they have to return it in October thus they kind of disclosed the fact they received it earlier. Sounds odd to me.
Yes...it wouldn't be very professional for a recipient under NDA to discuss this, even behind Internet anonymity.
My guess is that they borrowed the DTK from someone - if they have one at all that is