Working from the assumption of incompetence before malice, I'll go for a variant of your LPI discovery theory: the reporter watches the Apollo 8 Earthrise photo sim, goes to NASA's website to find out more, stumbles on the LPI gallery and assumes it was somehow related to the release of the Apollo 8 sim. I've previously seen most of the images presented in the DM story, so I find it hard to believe that those I'm not familiar with have somehow been suppressed until now (yes, I know, argument from incredulity...).