Blindness and Explode weapons

[Starfinder Casper]

So one of my players, whom uses a stearheart cannon, was blinded at the start of an encounter with by a trap and decided to bring up the blinded condition states specifically that creatures have concealment from him but a grid intersection is not a creature. Outside of hoping a player won’t meta game and target a intersection next to the creature because the player sees the map even though the character is blind, I had suggested treating the grid as if it had concealment and if missed, roll to see where the missed attack landed, another player suggested rolling perception to see if the character could pinpoint where the creatures were. How would/should this situation be approached?

[Nerdy Canuck]

In order to pull this off, his character would need to be aware of the creature's location - this can be accomplished with blindsense, or a Perception check to pinpoint the creature with an imprecise sense. Otherwise, the character does not know where the creature is located in order to target the grenade.

The player who suggested a perception roll to pinpoint the creature with, say, hearing, was correct per the rules; the relevant section is on page 260.

[BigNorseWolf]

Grid intersections don't have concealment. There's nowhere to go if they miss from the concealment.

Its pretty easy for their friends to call out "12 o clock 30 feet" and get a fairly accurate bombardment.