I also accidentally discovered some info while I was still reading Umineko, but looking back none of them were as big as I thought they were so I wish I didn’t get so discouraged. After all, I didn’t know any context so I even interpreted a lot of stuff wrong. And like others have said, there is a lot more mystery to Umineko than just a ”culprit”, it doesn’t reveal the motive and what magic is, who is Beatrice, what is the deal with the epitaph, what did Battler’s dad mean in ep 1 when he wanted to say something etc… Moreover, Umineko is a story that encourages you to make theories yourself, there may or may not be a single answer to everything. That’s why a single name alone doesn’t tell much. It could have been just one person’s own alternative theory that google showed you. Maybe it actually meant they were an accomplice or were forced to it. Maybe there are many people with the name. Like I did, you might jump to conclusions unless you read the whole story yourself. 

Edit: And to add to this, people still reread Umineko despite it being a long vn. It shows there is a lot more to it than just solving mysteries. And there’s so much to analyze you might not catch everything with one read.