The gate will stay closed, I fear.
The reason is this block:
Without it you could easily open the gate from the other side. Otherwise you have to pass 2 blocks (the solid and the gate block) in order to open it, which is too much to be possible, no matter what you do.
On the other hand it's indeed weird why the Super explodes in midair, but that is irrelevant in the end. There is no way to shot slightly below the solid block, pass the gate, and still hit the green switch, because they are on the same height, and thus if you miss the solid block you will miss it as well, no matter where the Super would explode on the other side. Only thing that counts is the height, not the blast radius of it, even though it looks close and possible.
For information, I actually tested this alot before entering Maridia in my RBO run around a year ago, since even though it's a detour from Norfair, it would still be faster because of avoiding of the slow water moves in the first rooms. I talked with catnap and Kejardon about this, and they both said it's impossible with that block before it. And I think when Kej says something about SM, then it's true, since he knows the mechanics of the game like no other.