There is more than enough proof there, you guys just need to watch the video.
Yes they both wear blue hats but pay attention to the physics guns, they cannot change the colour of it. It does not change unless the player dies, but in this video there is no death apart from Dodo's Smol has the blue phys gun and Emmit has the purple one. It is pretty clear who Dodo was killed by..
May I also add that if one of them did kill themselves, think about how quickly they would of got back to the location, there was no defib sound, no hyper tp and no tac insert sound. This really isn't hard to understand..