I believe that what you heard is correct. I interviewed up there a couple months ago in sort of a random way. I basically was in the Boston area and asked the coordinator if anyone at the HP program wanted to meet me. She set up 3 interviews. I had not even formally applied to the program at that point in the process. When I saw the same post that you are referencing, I emailed the Harvard HP coordinator and she told me that they were counting that earlier visit as my "interview."
By the way, I was also accepted at Hopkins.
