The goal should be to find a way to destroy the subreddit without getting removed as mods. Which should focus on killing user engagement through draconian mod rules. Like an automod that bans everyone that comments.
People laugh at the John Oliver thing for a few days, but the joke will get stale, that's when they need to stick to their guns and keep running it into the ground. I'd also suggest limiting posts to once an hour or something like that. Mods need to focus on making Reddit boring.
To add more context, currently Lemmy doesn't offer great moderation tools. So if a relatively open instance like lemmy.world interacts with beehaw, beehaw ability to shut down the 'few bad apples' coming from lemmy.world is rudimentary at best.
At a certain point, admins just can't keep up and have to make a judgment call. Either accept that trolls and bad actors are going to get through or cut off the source of the infection, regardless of whether or not that impacts regular users.
Beehaw has already stated that they're open to reconnecting once they have a better way of moderating and dealing with bad actors.
Many of datahoarders initiatives are pointless at best. Hoarding reddits data across a thousand personal hard drives that are inaccessible to anyone else is of extremely limited value. I've watched them perform the same action over and over, but most of the time that data never ends up in a new home. It just rots at someone's house.