Can I ask the question about the turn back a different way?
I guess I must be wrong, but I had understood the sequence to be a) rejection of return to LGA (involving a long turn to port off the initial near-northbound track and back on to a easterly heading); b) rejection of TEB, lying pretty much on the initial northerly track (though not aligned to it); c) decision to turn southerly and ditch in the Hudson.
The track shown suggests that the rejection of LGA came after the rejection of TEB - so, over Inwood Park, the the long turn to port onto a southeasterly course pointing roughly back to to LGA is corrected somewhat to starboard so as to to line up with the river. So, up to a fraction of a second before 3.29 did the guys think that a return to LGA was somewhat possible?
AGB