I don't think anyone has ever claimed that Porsche built it, Dave, so its certainly not a "Porsche" in that sense. That front to rear air induction system probably ensures that...
A little digging turned up this article in Euro Car from a few years ago, which sheds some more light on the history/mystery of the car. According to the article, Porsche apparently believes Waibel built it on an early 356 platform, Waibel said VW.
Looks like Waibel also built the two '48 show cars for Porsche, but those
are Porsches. (with no parentheses...)
http://www.europeancarweb.com/lookback/0211ec_waibel/#
Tim