I just saw this today for the first time. After reviewing a post in the "Close Votes" queue, I wanted to see how others had voted on it. When I viewed the queue history, I saw that multiple people had reviewed the same post; however, when I clicked my vote to see the other votes, I only saw my own vote. When I went back to the history page and clicked a different person's vote for the same question, I was able to see the other votes for that question. Clicking my own vote again still only shows my one vote.
I recorded a video of this process. It can viewed at http://sendvid.com/dkpzqx33