The questions were slightly different. Primary asked which were most meaningful to you overall; this asks "which was most meaningful in influencing your desire to pursue medicine."
So, on the primary, I discussed the leadership role that helped me grow most as a person, the scribe job that made me realize I could pull it off and enjoy it, and the research position where I grew as a communicator.
In this secondary, I discussed the first clinical experience I ever had - a volunteer position - and how it helped me to commit to entirely changing career paths and going for med school. Thinking back, is it now one of the most meaningful experiences I've ever had? No. There are many things which were meaningful for me as a person, but not my career path. And, since that volunteer position, I've had better clinical opportunities. However, it was crucial for sending me down the path I am on now, and I felt that was more what they were asking (plus that way I wasn't redundant!)