If I recall correctly, he had a rushing end right in his face and got leveled as he was throwing it. The ball just floated up there. He might not have seen Aiken loafing around at the 12 yard line. Belichek likes to screen his CBs, so Samuel (?) faded off Aiken knowing it was 3rd and goal from the 22, covering the TD but willing to give them the FG try if Aiken gets the pass. Evans had actually beaten his man. If Samuel didn't drop back and JP had more than 0.5 seconds to let Evans finish his route, it would have been a great TD.
The game was scoreless at the time, so trying to force one in there from 22 yards out was probably a bit too agressive. But, like you said, this team was 4-8. Why not get the TD? Plus, if it's an incomplete pass, they could trot Lindell out there to miss it from the 22. Six of one, half dozen of another.
The defense should have nutted up there, but let the Pats march down the field on an 80 yard drive finished with a TD rush by Brady on a bum ankle.
Those pointing to JP for this loss (not you Rubes) are being ridiculous. No running game. No O-line. Horrible playcalling. The kid is getting hosed. But he improves every game.