Greg did it to himself.

When he came out in 2003 he right away looked to shake down the weakest remaining link in his son's crew---Peter Forchetti---who was never any kind of tough guy, despite his girth. He naturally ran right to the Feds, who told him that he had to introduce Garcia to DePalma and claim he was his long lost buddy.

Greg was so predictable, the Feds were actually able to see this coming. Garcia's role merely helped them dot the I's and cross the T's on the future indictment.