I believe there's only a perjury penalty if you misrepresent the fact that you are authorized to act on behalf of the copyright holder.

So if you say, "I'm requesting you take this down because it infringes on Star Wars and I'm an authorized agent of Disney" when you have no relation with Disney, you're up for perjury.

However, if you say, "I'm requesting you take this down because it infringes on blahblah.avi and I hold copyright to blahblah.avi" which is true, then no perjury penalty. Even if blahblah.avi has nothing to do with the github repo being taken down. "Oops, my bad, honest mistake, wink wink." The person on the receiving end of the DMCA still has to jump through all the hoops to get their own copyright material reinstated.

So if you do your bot right, there's no penalty. None at all. If there is, I'd love to know about it, because these bots need to die in a fire.