It's easier to execute Saba based on a note, especially if the real 4th player (if the note isn't from him) isn't revealing himself. Although, on the other hand, he could insist on the execution, but maybe he doesn't want to expose himself. I don't know.
Added 1 minute later
Why did the commander decide to kill Menta on the second day?
Небо – угроз не слышит
Небо – ведёт особый счёт
Небо – тебя найдёт