The sloppiness is still a stretch given the resources available to ONI. Would it have been that hard to do some background research on space google or whatever to make sure all the facts check out? Hell, ONI has access to the best AIs out there. An AI could scour every network there is for all information regarding Eridanus and find any possible quirks that may poke holes in the cover story; the lack of boxing would certainly have been mentioned somewhere. An AI could also do this in the time it takes for a human to type "Eridanus boxing" in the search field (hell, all future search engines probably use some form of AI that can make the hits a lot more contextual and relevant than today).

And this cover-up wasn't just an insignificant side project for some intern to handle. It's about both humanity's greatest hero and concealing some of ONI's shadiest deeds. And they went through the trouble of constructing a relatively elaborate narrative complete with multiple actors to play out carefully built roles. So they way they'd cut corners with the very basis of the story is unbelievable to say the least.