DaveReidUK;
Ironically, the aircraft in question, which like most modern jet airliners was fitted with ADS-B, would have been squittering its position, altitude, groundspeed and ROC/ROD at half-second intervals continuously during the flight on 1090MHz...
Yes, concur, but only in FANS-1 areas. I am starting to come to the conclusion that the area in question is not FANS-equipped, (see comments re HF by Flapsnegative just a few back).
That is not an area in which oil wells are found. Thus, re "flames seen by TAM", there is a very outside possibility that such may have been picked up by satellite, although obscuration by cloud could be an issue.