From what I did find in the discords, officially:
Diamond apparently had a fight with Nightaku, In response Diamond apparently deleted every one of Nightaku's public messages from The Secret Family's discord server, unknown about messages in subscriber only areas.
Checking the Secret Family discord server, Diamond's not posted in a public section of their own discord in a few months while ignoring attempts to contact them, the discord itself seems functionally abandoned since the start of the month as well, excluding someone occasionally asking about/demanding harassment of Nightaku and someone spamming the music channel with YouTube links on a daily basis.
The only explanation I was ever able to find for anything relevant was a single person on F95 claiming Diamond Novels was sharing their accounts with other devs when someone called out a different game for using the Diamond Novels Itch.io account, their post was apparently deleted since then.
I did a lengthy writeup about this (The relationship between Diamond Novels and Nightaku) like 2 weeks ago with a large amount of links and screenshots around September 5th following HansDampf788's comment about the Subscribestar on The Secret now linking to Nightaku's Subscribestar (The URL itself is also suspicious but for different reasons), but couldn't bring myself to post it after 12 hours of doing research due to exhaustion, the feeling I was just being paranoid, and finally checking the relevant discords at the end of the research, as well as hope that Qwerfy's post was true.
Follow this up with spending the last 5 hours reviewing that research and rewriting the rant/research after checking to see whether or not this game was actually updated, not that I'll ever actually play it after the issue a while back with the randomly added discord integration that just advertised the devs subscribestar.
I backed up the rant/research on a google drive if it becomes needed/wanted, but it seemed fairly off topic for the question.
TLDR I convinced myself several users were the same person pushing out a few versions of a game then changing alias entirely to do it again for some reason. I stand by my paranoia on this.