I think the rumors need to be more general and less personal. This way there not pertaining to one character, or group of characters. The rumors could also help students with an investigative side find there way into some...well some precarious situations. A few ideas off the top of my head, which are not in rumor format.

- A rumor that there is some sort of buried treasure on the island. In the same instance that there might be a magical/mystical relic hiding someplace on the island.

- A rumor that the university or sections of the university are haunted.

- A rumor that there are secret tunnels/passageways located around campus. Some making it easier to move around the grounds, and possibly a few that lead to a way out.

yeah like I wrote there very general and at current very raw ideas.