The ADS-B transmissions likely stopped because damage from the missile's warhead disconnected the transponder from the GPS antenna that it uses (from earlier in this thread). If that was indeed the case, VHF communications would likely have been affected as well, which explains why there was no mayday or any other call from the crew. That picture of the cockpit and front section of the aircraft suggests that the missile did NOT detonate on the port side, although it's not really possible from the picture to say definitively that it exploded on the starboard side. That said, it would be consistent with the scenario of losing #2 engine with a resulting turn to the right. If the crew hadn't been incapacitated (or killed outright like MH17), they would also probably have continued the right turn in an attempt to return to the airport.
Given that the plane was flying at 275 knots and the missile was likely fired at it head on, it would make sense that the detonation occurred somewhere just aft of the cockpit, severing the connections to communications antennas and probably destroying #2 engine. There was likely a hydraulic system problem as well, and possibly a wing fuel tank puncture and fire.
I haven't posted enough to put a pic in here (or an URL), but you can see the 737-800 antenna locations at w w w.b737.org.uk/images/antennalocations_ng.gif