Ok so this is what I got now:
0x21D08 is current wins - single subway
0x21D1A is record wins - single subway
0x21D0A is current wins - double subway
0x21D1C is record wins - double subway
0x21D0C is current wins - multi subway with npc
0x21D1E is record wins - multi subway with npc
I didn't test but I suspect that 0x21D0E and 0x21D20 are for multi subway with friends
and last
0x21D12 is current wins - super single subway
0x21D24 is record wins - super single subway
didn't test the others in super yet (i might do it now and come back with the exact offsets)
I suspect that 0x21D2C could be a flag that sets either if you are still in a challenge or not (since it changes from 00 to 01 as far as I saw)
either way, i saw that if you change the values here, they don't change the flag of super subways, i might have to check the events offset and compare it to my clean save (no subway battles)