Must be something special - 7 close votes are not enough?
If you look at each of those users you'll notice that 3 of them have less than 3,000 reputation. They can't vote to close.
When you have less than 3k reputation the "Close" button in the LQP queue reads "Recommend closure" and flags a post for closure with the specific reason they chose.
This is similar with the "delete" button. Once you get 20k it will change from "Recommend deletion" to just "Delete" (providing the answer meets the criteria for 20k user deletion).