They actually did that un purpose, when you see Leo throw it he knows that's gonna happen. The spot just can see through the wall because of the difference of level in the flor of the site
But it don't make sense yet, cuz Sayf was in the same level as the spot and fully behind the wall, he was not able to see it and shoot, because the spot wasn't visible and he was revealed either way
But the wall was on a lower level so it saw him from the top part. ik he doesn't see it on the camera but that's probably just because the top part of the viper wall works weird