Okay but seriously, why did Matt put a code on his tombstone that only two other people in the galaxy can read? My thought?
AT SOME POINT HE WAS REUNITED WITH HIS DAD.
Why did he even have a tombstone to begin with? Perhaps the Galra attacked at some point and caused them to separate again. For some reason he assumed his father would check the memorial because I find it hard to believe there’s anyone in the resistance that doesn’t know it exists and then instead of finding his dead son he finds his code :D
I mean, his father is literally the other person he knows in space that knows the code so why else put it on his tombstone?
Of course this begs the question of why Matt never mentions he met up with his father to Pidge. Perhaps he saw no point? I mean, this theory is assuming him and his father were separated so maybe he didn’t see the point in bringing up. You know, why give her hope just to take it away sort of thing?
Of course it could also be as simple as Matt assuming his father will be rescued by the Resistance and then joining them like he did but that still begs the question:
WHY IS THERE A TOMBSTONE IN THE FIRST PLACE???