Since part of the fraud revolves around intentionally delaying the delivery of hardware, his role at BFL would put him smack in the middle of things despite the fact that he doesn't own the company.

I think it would boil down to:

1.) Were there really delays in manufacturing the Monarch?
2.) When he made the public statements about delivery times, was he intentionally misleading customers?

The inability to deliver useful hardware in the stated time-frame would rest at the feet of the person in charge of such things, which would be Josh methinks.  That would put Josh's role in the center of the fraud.