I don’t understand your point.

The court ruled that it has jurisdiction over the case, and that some of the allegations are plausible. How are they not investigating Israel for the crime of Genocide?

Again your use of language is loose. It's yet to be established that genocide is occurring, so how can you investigate it?

Is the misunderstanding in the meaning of the term investigate? It very common for justice systems or law enforcement to investigate whether a certain crime falls under a given category, for example Hate Crime.

Here is one example: https://www.msn.com/en-ca/news/canada/comments-at-pro-palest... The police does not know as of yet whether this protestor was guilty of hate crime, but they find it plausible, and are investigating.

Now this example is of a local law enforcement, which has pretty liberal laws on what it investigates. The World Court however needs strong conviction to even accept a case. The court did rule that the accusations are plausible and that they have jurisdiction over it. In other words, they are investigating whether Israel’s conduct falls under the crime of genocide.

Perhaps in the narrow technical meaning. But how you present it has great PR value.

I'd like to announce that I'm now investigating @runarberg for <despicable crime>.