On the discord, one of the employees dropped in to say that no one was hurt or sick, but at this was all they would say on the matter.
Honestly my guess is that Brandon might have realized that his plans for the cosmere might be a bit too ambitious, so some of the things that have been in the backburner for a few years are either being cancelled or co-authored.
Take it from someone who has spent periods of his own life working far too hard and long. When you are in the middle of it, you push through, feel invincible, and are proud of your own work ethic. However the exhaustion catches up to you, and not in a fun way. Honestly I don't know how the guy manages the things he already has on his plate. So if he needs to scale back or even take a break, id say he has more than earned it.