Here’s a post with more details - yes, seems like the post I quoted is just people making a joke out of the original Latin phrasing of the payroll, which for some years was written “to the custodians and the cat” rather than the presumably intended “to the custodians for the cat”.

True haha. Here’s a post with more info - I take it the original wording from the Mastodon post I quoted was just being cheeky about the cat technically being on the payroll. One supposes that the cat’s human aide took the money on behalf of their illustrious master ;)