Actually, I think they’re greatest nightmare would be losing their tax-exemption in the US.
All indications strongly suggest that the Org’s business model has become dependent on it. Lose it, and the WTS goes broke trying to stay in the black.
If it goes broke, it can’t function. If it can’t function, it can’t survive.
And if it can’t survive, it can’t really be “God’s Exclusive Earthly Organization”, can it?
And that prospect is unthinkable.
By that chain of logic, loss of the WTS’s tax-exemption threatens the very existence and legitimacy of everything they live for.