Only if you assume that (a) donors are actually aware of an 85%:15% split in the charities' disfavor; (b) approve of that. I would expect the naive assumption to be on the order of 90%:10% in charities' favor, but maybe that's just me.
Now, their donation pages for separate charities eg http://www.givewell.org/international/top-charities/villagereach/donate do state that the donation is direct to the charity, which is .a good thing.
So it's "I'm willing to take your money for me, but if you want to give it to X, give it to X directly" vs "I'm ...
Alright. You've given an explanation here that seems reasonable to me, and you've continued to run GiveWell for significantly longer than I would have expected if you were just in it for yourselves. For what it's worth, I'll give you the benefit of the doubt and I wish you well in your mission.