I have seen quite a few watchtower publications on Hoarders, hard to say if they were JWs or just took the literature to add to the hoard. It wouldn't surprise me if there were hoarding JWs, they seem to attrack the dysfunctional.
Hoarding is a very difficult to treat mental illness, no elder would know enough to deal with the behavior, the JW black and white thinking would probably just tend to make things worse. To a hoarder, throwing something away produces a very strong fear response, much like you would feel if you encountered a snake, it arouses a flight or fight response.