Not considering the costs of hosting infrastructure for downloads, developing Fediverse integration in software is an extremely complicated task, and retrofitting it into existing software is no joke.
A more realistic starting point is probably to follow them on Mastodon, ( @Retromags ) interacting with their posts and trying to spread them, and to try to build up a fediverse presence for them. Then eventually, if they find that they get the majority of their interactions through the fediverse, they might consider merging their comment sections.