A list of ALL donors does seem very unusual - and if there are as many donors as the cash inflow might suggest, quite time-consuming to review.
I have to wonder as well if the IRS isn't "on to something" about a particular donor or perhaps type of donor.
If this information becomes public (my opposition notwithstanding), it would come in quite handy for someone looking to bring a class action against JW on behalf of contributors who made contributions based on false pretenses.