Raid On The Cult Compound Day!
The ATF is going to raid your compound at 5 PM today. You have to convince your followers to kill themselves before then. Trouble is, while you had planned for them all to kill themselves from the get-go, you expected to have a few more years of brainwashing to convince them that mass suicide was the only way to go. Right now they're all with you in the whole "defend the compound" scenario. But to walk in and say, "I know what, let's all off ourselves," it would really be coming out of left field.
You could try to just rattle of a litany of really depressing stuff and see if that works. Show them a slide-show maybe of puppies being punched in the face or an "According To Jim" marathon. Or how about this? As the leader of the cult, all of your followers wanna marry you, correct? So why not write each of them a "Sorry, I've just always seen you as a friend" letter? Nothing makes people commit suicide like unrequited love.
If it gets to around 4:30 though, you're going to have to kill them all and make it look like a mass suicide instead of a mass murder. Best way to do this is if you slit all of their wrists and forge "goodbye cruel world" notes in each person's handwriting. Not feeling so great now, are you Oh Great One?
Happy Raid On The Cult Compound Day!