No, unfortunately nothing can be done at this point. The investigation into this matter has been poorly done, cause if it were thoroughly done properly I know what the outcome would have been.
Unfortunately some people get paid to do nothing.
But, you are right about one thing, it's best to just keep to certain people only, those of which I trust.

I know there has to be something that can be done!! .. don't stop totally, just cut down, only do it with certain people you trust!

Happy Easter To U