I seriously doubt that they have the cash flow to pull 5 more aircraft up from the ice. 300 volunteers is great, but unless they have the money to support that level of crew, and the actual recovery, it is just words. Admittedly, Schoffner's people spent oodles just trying to find them, and that part has been somewhat eliminated, they still need to asertain the exact final location of the remaining 5 aircraft.
As for the B-17's, well, the one they went down to was so badly mangled from the ice pressures and shifting that they were deemed unusable if recovered. The dorsal turret (top shell only) was removed from the one B-17 they went to, and was sent to Tom Reilly's Vintage Aircraft to be restored. It was a mangled mess, and basically became more new than it was original.
I guess after being in the restoration business for close to 15 years I can say that all things are restorable, it's just how much history actually remains and when does a "one off" restoration begin? I'd say that it is up to the person, but I'd like to think that anything containing more than 50% of the original structure or all the usable portions that add up to 50% should be considered "original"