I definitely smell "media spin" all over this.
Regarding the behavior of the officers, I have to believe that they deal with that stuff dozens of times a day and this is just one. I bet in any of your professions, you come across "that person" who just makes you :facepalm: Well, if this kid was being threatened with the lives of his sister at stake, well, he still has a choice. Albeit an unpleasant choice. I don't see the officers forcing him to drink it. Could the officers have handled it better? Maybe to even probably. Worth getting disciplinary action against? IMO, I don't think so.
With the speculation of the kid doing this under the threat of his family aside, the saying "play stupid games, win stupid prizes" comes to mind.