So now that the stream has ended, I can link the part of the stream where everything goes wrong:
On listening again, it sounds like he didn't say "carry them one at a time!", but he said "it was one of a kind, and you broke it!".
Sounds like it was a piece of Sonic merchandise that was either a relic at the office, or it was even going to be used for some upcoming promotional event. Sounds pretty serious.
Alex gets super mad. It's not just this part too, you can hear him shouting at later points in the stream outside the stream room and Aaron had to step outside to calm him down. While that's happening, Sergio (the well-known intern, he's been there for a while) starts talking to the chat and mentions that Alex really needed to calm down.
Also Aaron mentions at an even later point that he couldn't find Jerry at his desk so...yeah. I think he got the axe.
Man, that was surreal to see. Again though, Aaron handled it so well.