Gonna try to explain from the beginning, at least from what I remember. He posted an update about what his sources told him and said the following:
Confirmed:
1. There’s 108 Stages
2. Ken, Shadow and Incineroar should be in
3. He’s confident enough to say after talking to enough people that Isaac and Geno are in, but if he finds something else out about them he’ll update us.
Deconfirmed:
1. There’s no Minecraft content.
Unconfirmed:
1. The Banner itself. He said he was told the banner has some oddities and elements that are different than the one people have seen.
Then he posted his own personal opinion that he thinks the banner is fake, but quickly realized that people may take what he said the wrong way so he promised to explain later but before he could, he got harassed for it. Then later he explained that while he’s confident that Geno and Isaac are in, he doesn’t want his word being taken as gospel. And that he didn’t deconfirm the other three characters (Chorus Kids, Mach Rider, and Banjo) whatsoever. And he tried explaining his earlier comment about the banner, where he considers unconfirmed but personally thinks its fake, but people harassed him for backpedaling. Later on he also told someone privately that Chorus Kids are also in and that one of the characters on the Mural are an assist trophy (Though, I think he was speculated with the latter). Eventually due to the harassment he privated his Twitter.
Basically, he did everything people would want from an insider by being transparent with us, updating us and answering our questions, and even telling us don’t take his word as Gospel, yet he got harassed for just personally thinking the banner was fake.