There is tangetial data that supports the notion that perhaps Jack and Gross were working a bit more in tandem than you might think when you see the number of former GE folks that went to work for Idealab, particularly the movemnet of GE fleet people to Idealab's Carsdirect operation. Don't know where it leads or what it says, but it is a curious fact.
The only explanation that fits the facts, IMHO, is that Jack rented his "good name" to this scammer.
Given Jack's already immense wealth, I am unable to rationally devine why he would do this.
Knowingly using ones' "good name" to entice unwary Joe Sixpacks to invest crosses a bright ethical line in my mind.