I was mistaken about the action that would need to be taken, as I thought a record would've been generated automatically (which makes sense since they might need to step away for a moment or something). I'll fix the original post I made about this.
That said, in practice, I'm sure most Approvers would not skip over that button to avoid causing offense. Otherwise, the images will pile up in their queue and it'll make things harder for them.
I also don't see the problem with "disinterest." It's a statement about the Approver, not the post. If we really wanted to, we could change it to something like "post #xxxxxx was not approved (skipped)" to remove the dis- prefix, which suggests a negative action instead of the absence of a positive one. It would also state the actual action instead of making inferences of the Approver's thoughts. However, this is mostly nitpicking and really shouldn't be a priority.