Finally, who is to say that TIEs don't have ejection systems? While the only canon occurance is the TIE/sf from The Force Awakens, this game could include it.
In ESB you do actrually see a pilot fly away from his TIE when it get's smashed by an asteroid (1st or 2nd, at work so can't check) A TIE pilots flight suit is vacume rated so one could survive. Also who is to say that a destroyed ship always explodes. ROTJ a Y-wing spins out of control (then crashing in a ISD) when hit. Red leader in ANH only died when he crashed into the death star. Plenty of (legends) books talk about TIE's having being destroyed by getting wings or engines shot off and being counted as "kills".