Tommy -
If I had to guess, the developer probably overleveraged itself, and is now either a) refinancing, or b) looking to sell. In any event, I imagine he is not in a financial position to pay Fazio, especially ahead of the bank. Therefore, this move, which is nothing groundbreaking, is merely to preserve his right to payment. Although he is an unsecured creditor, he risks losing his claim if he doesn't take the administrative step of filing a lien on the property.
I'm a bit unfamiliar with the practices of the industry, but I imagine what you are referring to is a construction bond purchased by the contractor to secures the developer that if the contractor defaults the subs will get paid, and not come after the developer. I don't think the developer gives any return assurance to the contractor or Fazio by way of bond to secure payment to him. Hence, why he's filing his claim, which is a lien that will attach to the property and will travel with the land until the debt is discharged. If this guy were to file bankruptcy, Faz would likely be looking at pennies on the dollar in the best case scenario.