Yes, Herb Greenberg is slime. He has been part of a number of coordinated short attacks on various companies. You can't believe anything he says.
On the other hand, coordinated short attacks can have impact. (Although they usually go for smaller prey than BAM--like Green Mountain Coffee and HerbalLife--shorts consistently gear up for Walmart and fail. However, one has to respect the recent Apple "Kill.")
Greenberg is more likely looking for press time connected to BAM's Brazil issues.