Obviously DA has decided he wants to go in another direction. He has (guessing) no intention of playing it out another year.
Pierce is likely gone, which means KG will want out. I guess KG decided he wants to play one more year, but will not do so for the C's without Pierce.
Doc and KG appear to be bound at the hip. They only want to coach/play together. Not surprised, as they are good friends. This is particularly the case with KG. He's pretty much said in the past, point blank, he will only play for Doc.
Not sure where Pierce falls in this, but I wouldn't be surprised to see him end up with the both of them as an MLE signing.