Sounds like Jefferson K is vamoose.
Koulibaly, isn't likely leaving. There is a small chance, almost anything is possible, just not likely.
The reason it's not likely is that when Flowers is gone, the guard rotation is likely: 1.PG: Starter: Tyrell Roberts. #1 back up: Koulibaly 2. SG: Starter: Noah William's: #1 Back up: Koulibaly. 3. Starters: Bamba, Rodman. #1 back ups: Bamba, Rodman, whichever doesn't start. Jaki will sub at the 3,4,5 spots, wherever can find him playing time. Ryan Rapp a #2 back up at the 3 spot.
If Rice is good enough, Rice backs up Tyrell at the 1. PG spot, and Koulibaly is Noah's back up. Rice not good enough, Koulibaly backs up both Tyrell, and Noah, and Rapp could end up backing up Noah if Koulibaly is Tyrell's back up, and Rapp is good enough to back up Noah. Also if Bamba is not ready to start at 3 spot, then not only would he back up Rodman at the 3 spot, but would also back up Noah at the 2 spot, if Koulibaly backs up Tyrell at the 1,PG spot.
The Rotation at the 1,2,3 spots, could easily be Tyrell, Noah, Bamba, Koulibaly, Rice, Rapp. Easily 5,6 deep.
And Dylan, is not likely to beat out anyone, whether starter, backup, etc.
And yes, WSU will get a transfer guard, but it will probably be a Sophmore transfer guard with 3 to play 2,3, who will take 1 year to develop, likely won't replace Tyrell, Noah, Bamba, Koulibaly in the rotation.
WSU probably won't get another grad transfer guard like a Mike Flowers, because it's not needed. WSU needs to recruit for 1,2,3 seasons down the road, not for this coming next season.
So Koulibaly, should get LOTS of playing time, and production, as a #1 back up, at 2 spots, 1,2 spots.
And Koulibaly will be a very productive starter, during his senior year.
And that's why Koulibaly won't, shouldn't, probably won't transfer.
And that's why WSU probably won't get another grad transfer guard like a flowers.
And if Koulibaly doesn't produce as a #1 back up, Rapp probably could.
Rosario is more likely to transfer, after that, maybe, maybe not Rapp.
Only way Koulibaly transfers is if the right team that could start Koulibaly, and offer Koulibaly a NIL deal, etc, goes after him. But even then, there is a very small chance Koulibaly might even still stay.
The other factors is that Kyle Smith has been good at convincing players to stay, not transfer. And since WSU would likely finish 2,3,4 in conference, 13-7,14-6, in conference, 21 to 25 wins, 2,3,4 Pac 12 tourney wins, 4,5,6,7 seed, 2nd round, sweet 16, Elite 8 in NCAA Tourny, that's another reason Koulibaly probably doesn't transfer.
But IF,IF Koulibaly transfers, then WSU would probably try to find another grad transfer guard like a Mike Flowers
So WSU really needs to recruit for the season after this coming next season, as after that season, WSU is going to lose a lot of key players.
So WSU likely won't lose any key players, and if lose anybody, it would be deep bench players, and so WSU probably won't need to recruit a player to have a big impact player for this coming next season.
So WSU will get Solomon Ominu the Nigerian Big, Dlyan, and probably either a Transfer Sophmore 6-6,6-7,6-8, 3 spot, or a 3 spot, 6-6,6-7,6-8, HS recruit, or a soph transfer combo 1,2 guard, or a HS 1,2 combo guard, and either a preferred Walk on either 3 spot, or 1,2 combo guard.
Basically 3 scholly recruits, and 1 preferred Walk on.
And it probably won't be a high ranked class, but will be average class, that helps team in future years.