Thank you for the information, Robert! Also, I just now realized that I had not really addressed your question about what constitutes cultural humility:
Cultural humility is a client or patient's perception of their treatment provider as inclusive, understanding, and welcoming toward their cultural background and beliefs, especially as those beliefs relate to treatment. According to Hook et al. (2013), who introduced the construct of cultural humility, culturally humble clinicians are a) aware of their own limitations in regards to culture and genuinely seek to understand clients’ worldviews and b) accepting of cultural differences and conduct counseling in which clients’ goals and worldviews take precedence.
So in your example from college, I think cultural humility could certainly have been a part of that relationship, in the sense that your counselor had empathy for your situation and (hopefully) respect for how you experienced it (and also how your experiences might have differed from his own!).