I am mostly in agreement with sbf on this, except I do not think they are close to a financial collapse as yet. Limited financial info, such as the UK accounts, suggest (in the U.K. at least) there are still investments being held by the Borg, although these have decreased. Further, I doubt that the Borg has significant external debt, and I haven't seen any evidence otherwise. Most sudden and outwardly unexpected financial collapses (but not all) involve a significant amount of external debt.
I suspect they are making losses, and this is using up their reserves, but there is a while to go, yet.
One question I don't think anyone has addressed in detail, is what would a "financial collapse" look like. For a religious institution with no significant debt, there might be little to see. There might not be any sudden default. I would have thought it would be more of the same as we see now; more asset sales and bethel layoffs, and only very core activities continuing. Not an actual collapse; more of a "financial fade".
It is not as if JWs are going to wake up one morning and find they have been merged with, eg, the Mormons. I think the average JW won't notice much change, in a "financial fade", apart from less micromanaging from Borg Central. I think it would mostly affect bethelites and various others feeding off the teat of the Borg. The GB might get a shakeup, or even replaced, and many senior managers will go, but the Borg would probably continue on, with whatever donation income is available.