It’s kind of hard for me to give a thorough reply without knowing the details of what your specific “Safe Space” training discussed and how it was presented, but I guess I’ll share my own experiences, as I recently graduated from college (a public school) and have been through different “trainings” (sexuality, gender, race/ethnicity, religion) as a part of membership in student organizations and student government.
I think that one can gain a lot from the experiences, even if you don’t agree with everything that’s presented, but it requires an openness, patience, and charity in order to do so. I learned a lot about the experiences and struggles that people of the LGBT community go through, even though I still don’t approve of how they (or at least some: it’s important to remember that not everyone with SSA will act upon it) choose to deal with their experiences. It definitely increased my sense of compassion and respect for those with SSA and those who are openly homosexual because they struggle a lot, and that isn’t often recognized, which is in line with the Catechism teaches (
C.C.C. 2358, apologies, I’m not quite sure how to format citations of the Catechism

). It was also an opportunity for me to share my own beliefs and perhaps clarify what the Church teaches in this regard.
In my opinion, the main point of the training (at least the trainings I have been through) is to learn more about people who have different backgrounds, be able to share experiences, and come to an increased sense of respect for other people despite disagreements that we have.
Now to address your original question. If the training was presented in such a way that those putting on the training were forcing you to accept that homosexual behavior is acceptable, I do think that’s grounds for legitimate complaint, especially at a Catholic University. However, personally I feel that there is room to adapt such a training to Catholic teaching.
Also, from the university administration’s aspect, there are reasons to have these kinds of trainings for their employees (especially RAs). As an RA, you are somewhat responsible for your residents’ well-being and for what happens on your floor (or building, etc.). From an individual standpoint it helps RAs have a better understanding of different people and so you are better able to serve their needs, and in some extreme cases ensure their safety. Another reason is that (disclaimer: I’m not familiar with legal procedures, so this may not be totally accurate, feel free to correct me on this) I think there’s also a belief that it might help in the event of a lawsuit: if a lawsuit came up and the university did NOT provide this kind of training for employees, the complainant could claim that the university does not do enough as an institution to prevent discrimination.
So in short summary (please forgive the length of the post

): There are reasons that such training is held, and there are positive things you could take from a training if you are open-minded, patient, and charitable, and make your own contributions to the discussion. If you do feel that you have a legitimate complaint or suggestions (suggestions are more helpful that simple complaints), it’s probably best to go first to your supervisors and share your concerns.