This doesn't look like the same person as Crooks. I saw a video of someone that looks similar to the dude in this picture make a troll video after the fact saying HE was the shooter and he's "still out there". It very much seems like either this same person made an IG account immediately after to mess with people or someone else saw that video and chose to make this account to mess with people. Either way, I don't think this is the same person as the shooter.