[@AngelofOctober]

If they do not have a teacher yet have access to the knowledge then it may be the situation of comprehending the knowledge. While they may understand the basics and can understand the in depth matters, I imagine the actual function of any singular spell isn't the same as another. One may require something the other does not. A teacher would help with the understand due to already having a grasp on what is necessary for the processes of that spell. They could still learn the spells from the knowledge, I just doubt that they'd learn as quickly.

As for the hiring matter, it is an impasse. Though, I imagine they also do not wish to send rare Chimera level Swordseekers into an unknown land and without knowing what exactly they are trying to do. Without information, they could possibly be sacrificing some of their best on a suicide mission. That would do poorly for their company.