A FOIA request won't make them put the blog posts back up. They just have to provide you with a copy. And they can charge a fee to cover the cost of doing this. So, given that the posts are already publicly available, it seems like a waste of your time and money.
Obviously, FOIA requests are meant to be completed using the organisation's own records, but is there anything that's stopping them from just replying with copy-pastes of the post text from the Wayback Machine?
The paper trail that can be made available and/or added as evidence or a factoid in a historical record. Maybe with enough accounts people will find a way to avoid a repeat in the future. Maybe/maybe not, but they definitely won't know to change anything if there is no record of it being an issue in the first place.
Thank you for pointing me to that. Still, strong disagree it applies here, so I'll counter with a quote from the second part of a three piece opus, in a photoplay long ago and far away: