Well, they are damned if they do and damned if they don't, aren't they?
They have to do something, I wouldn't put it past them, but it's a complete reversal of everything they have ever said about donations, so it will cause a stir. People are already giving huge amounts of personal time and energy to the Watchtower due for meetings, field service, study and congregation duties, with not much coming back in the way of moral support or spiritual sustenance. Many don't make a lot of money, tithing will be a hardship for a majority of JWs. Some may well decide it's just not worth it. They do risk people leaving or giving up and donating nothing, they have to be aware of the possibility.
I am sure many people have already had doubts because of recent events, you have to wonder what will be the tipping point, what one thing will cause enough people to become disgusted and leave that it puts them in a death spiral? How many are already only staying because of family? How many have doubts they are keeping to themselves? How many will leave if enough family members leave?