Unlike the Secret Keeper Wizard College, the apprentices of these two lacked a leader with enough prestige among them, hence, the moment they entered the Secret Realm, the struggle for leadership began for both colleges.
After vying for leadership, both colleges, following the regulations of the White Wizard's Manual, began to build defensive measures at resource points, which took a considerable amount of time.
Upon completing these tasks, there was more internal squabbling within each group, and they ultimately decided to send people to the resource point where the Secret Keeper Academy was located to exchange information and form an alliance.
The timing just happened to coincide with the end of the great battle between the Secret Keeper Academy and the Black Wizards.
"Rules are rules, without a commander's order, none of you can enter."
The guarding White Wizard said sternly to the outside White Wizard Apprentices, completely disregarding their protests.