As a former USAir pilot, I watched this with interest. About the only argument that I heard from the pro-ALPA side was that an independent union was incapable of providing the support that a national union could, forgetting that there are some very successful independent pilot unions (SWAPA, APA, UPS). Not once did I hear any acknowledgement of the very visible mistakes that ALPA had made over the years (pensions, B-scales, crossing of other unions picket lines, age 65 and the general fall of U.S. pilots from the highest paid to some of the lowest in the world, etc.) or that some kinds of change might be appropriate. Add to that a large enough number of pilots who thought that they really had nothing left to lose and the result is not surprising at all. While I question whether USAPA has a legal leg to stand on regarding overturning the arbitration, there is a large enough number of pilots from the east that don't have much else to lose by giving it a try that they were able to de-certify the union. This in itself is a prime example of mismanagement of the process by ALPA national (and ALPA USAirways).
On this and other forums, I have heard more angry and sometimes incomprehensible rants from the AWA pilots than from the east side. While I acknowledge the argument that the arbitration was agreed to and binding, I have never once heard an AWA pilot acknowledge that a large number of east pilots might have been unfairly disadvantaged by being put below west pilots who had less than 2 years with the company or who were not even out of grammar school when those east pilots were hired. By not addressing that issue, whether they legally had to or not, they helped to achieve this outcome.
Regarding the west pilots not contributing to the new union; I'm no expert but I believe that laws exist (or it just might be contractual language - I'm not sure) that require even pilots who choose not to join the union to contribute some amount for the administration of their contract or face termination.
Whatever the outcome, I don't think that anyone will disagree that this has been a complete mess - and it's a mess that certainly started with ALPA.