Sorry for the bug, I've noted it and will have it fixed asap! You should be able to reload your save prior to the 'warning' and just re-enter the lab, just don't go back to the 'warning' hall, and you should be good to go.
As for the 'warning' itself, well, that would spoil the mystery, wouldn't it? ;) (lol jk i just looked up rgss3 coding on google ;v;)