It’s possible for the first live guard you encounter to drop his gun, so it’s also possible to get the Glock before the crowbar.
Also, it’s a glitch, but the if the dead guard in the laser hall is disturbed with a prop, sometimes he’ll pop up to shoot you and the laz0r will kill him, dropping his gun.
But you’re supposed to encounter the Glock within minutes of the houndeyes.