I'm intrigued that you're splitting your donation. Are you doing it because you're truly undecided which is best and you'd rather not pay the psychological cost of feeling like you're "not covering your bases" (https://www.jefftk.com/p/give-to-multiple-charities)? Or do you think you'll influence enough of other people's donations that you'll hit diminishing marginal returns on the individual charities (which is why GiveWell split its recommended allocation this year)?