This is one of those situations where the WTS and the elders are holding all of the cards. I believe that Bill's options are very limited. From a legal perspective, I'm sure his attorney has assessed his probability of success in a civil complaint related to the judicial action. They are poor in my opinion but nothing would please me more than to be wrong.
If I found myself being called before a judicial committee and it mattered to me whether or not I was disfellowshipped, I would be inclined to make it perfectly clear to the local elders that I would positively sue them personally, not the Watchtower. In Bill's case, this is not going to work since WT legal is already involved. I know for a fact it has worked in a few other cases. When local WT elders who have a few dollars in the bank begin to realize that they could lose those assets if they make a mistake, some may think twice and back down.
Here is one other possibly helpful tidbit. If you have quit associating on your own, and you have been out of the organization for a few years, the elders have the option of not forcing the issue. If they do, what do they accomplish? In most cases, they would only be acting to strain family relations with your JW relatives. A civil rights attorney mentioned to me that there is some applicable case law about "alienation of affection" that can come into play. I still have a letter from him somewhere on that topic.
It is probably just a matter of time before the WTS commences with a full blown witch hunt and with the "dumbing down" of the organization over the years, some of the local "meathead" elders (the type that disfellowship JWs for reporting molesters) are sure to make serious mistakes in the handling of judicial matters. That could open the door and allow some inroads to be made into the WTS legal firewall on disfellowshipping.