Because GL can't do this against Raven. Green Lantern's ranged options are highly punishable by Raven and give her unblockables (fire out a rocket, prepare to get it absorbed and an unblockable come your way that you need to avoid), free trait, stupid amounts of meter, full combo punishes, etc. GL has to keep the close range pressure as that's the only way he can hope to beat Raven. For part of the first round Sabin tried widening the distance when he got the life lead and was completely blown up for it with pillar/crush traps, shadow/crush traps, raw Soul Crushes after his projectiles wiffed, etc etc. As for him dropping the combo at the end, that doesn't mean anything in the MU discussion. And in match 2, one mistake put GL full screen and he never really got back in.
Blind Man's biggest problem in match 1 was "slightly" (seriously...) overestimating the range of Raven's d1 which he was rightly being blown up for