The board of directors have no jurisdiction to investigate an "influence operation on their CEO", and even if they did, they have no power to do anything about it. Their jurisdiction is within the business.

If this was primarily an investigation of the external actors, this would be talking about what law enforcement are doing.

The wording of the announcement is pretty neutral but I think it's clear what is within and without their bailiwick. The title is a much more informative description than "Statement from the board".