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If they're talking about static loads, the stated .3 to .8 g would be several times too small even at the upper end to cause failure. If, on the other hand, the vortex initiated and sustained a harmonic oscillation of the vertical stabilizer, it could have led to a dynamic instability called flutter. The key issue would be whether the vortex could act as a load factor that stimulated a resonant frequency of the vertical stabilizer. The controls software of the A/C may have contributed to the problem if it didn't properly act to dampen rather than amplify the oscillations.

There's a famous film of the Tacoma Narrows Bridge that was built without consideration of resonant frequencies. Shortly after it was completed in 1940, on a windy day, the bridge began to rock up and down, with the waves in the roadway reaching several feet between crest and trough before the whole thing collapsed. It's believed that vortex shedding from a natural formation provided the periodic input that resulted in the bridge's collapse. Go to Tacoma Narrows Bridge Failure for a technical explanation.

Did the bridge take a while to fall apart. It didn't happen within a second or so did it? Also didn't it break up into chunks instead of the entire tail falling off the plane? Wouldn't the bolts holding the tail on break first considering they are the weakest point?

"The controls software of the A/C may have contributed to the problem if it didn't properly act to dampen rather than amplify the oscillations."

I've been an aircraft electrician for 20 years now on A-6E, F/A-18, F-16, and now C-130 type aircraft. Your entire statement was exceptionally well written; quite expressive. The only issue that I have is that you have made the assumption that stab aug failed. If there was a massive failure of all fcs channels then it would be recorded on the flight data recorder.

I think it was sabotage.