Some folks would probably rather see it all scrapped rather than end up "somewhere else" (unfortunately).

As you said, WFIM did indeed publicize what was going on and it's quite likely that "other Northwest museums or historical societies" did indeed know about the situation. It's also very likely that none of those organizations had the funds to purchase or the space to house any of it, or even the resources to properly maintain what they did acquire in addition to what they already have. Otherwise, one or more of them probably would have made an offer. It's not like these guys have deep pockets or lots of rich supporters, after all...