I find it hard to believe Desir wouldn't have expected this. It's not like Adjest would be different from the other Alpha class students by actually wanting to give the Beta students a fair chance to advance. She's the same as the rest of them. If there's one difference, it's that she has real skills, not only empty arrogance. So, Desir would have obviously realised Adjest wouldn't simply remove so many Alpha students from the game that Desir's team would automatically advance.