I didn't say anything about homing. Use a raycast, starting at where the grenade 'exploded' and ending where the player is located. If there is any obstacle in between these two locations, no damage will be dealt. Where the forget did you get homing from?
EDIT : I get what you're saying, doing this would result in always getting hit, with no possibility of it missing them. Though that's not what I think of by 'homing'
I still think a ton of projectiles everywhere is a waste. Maybe for each player found, a half dozen or so are fired in the approximate direction of the player? Would allow players to hide behind walls, with the possibility of not getting hit, and without using an extreme amount of projectiles.