[JohnnyP]

It’s a flashlight.

You can see the light in this video:

https://gfycat.com/OddUnitedAmericanratsnake

The light hits just above the elbow of the left arm of the guy in the dark gray suit. Just before the video repeats.

[Ditter]

I first thought it looked like a flashlight, it also could be an epi-pen but why would he be carrying a flashlight?

[jetson]

Very strange video. That black guy is extremely odd. Why would he have a little flashlight? It looked like he was trying to hand the thing to her.