The truth is that the SEC had no idea about the unregistered shares at that time and if they did it should have been made public!
Of course they did. Anyone with a functioning brain who'd followed the story did. Here's what you just don't GET: they had to PROVE A CASE. You can't just waltz into court and say, oh, we know Urbie was issuing unregistered stock. They had to issue subpoenae for the TA logs, for the opinion letters, and all the rest. They had to find out to whom the stock in question had been issued, and when. And they had to find out who those people were, and what they did with the stock, and so on.
That does not happen in a few weeks, or even a few months.