if you check out my previous two video analysis posts you will see that those videos are showing a flashing light that can be seen on the hotel before, during and after the shooting:

https://steemit.com/news/@ura-soul/las-vegas-video-showing-why-the-flashes-from-the-4th-floor-of-the-mandalay-bay-hotel-were-not-from-a-gun

https://steemit.com/news/@ura-soul/video-analysis-of-light-flashing-on-the-outside-of-the-mandalay-bay-hotel-before-the-shooting-started