Your concerns are totally valid. It is difficult to imagine a realized Virgin Nigeria considering all the hurdles (and misconceptions, if I may add) in Nigeria today. We must all remember that Nigeria is still recovering from decades of corrupt military rule.
I think you would agree that Nigeria's private sector is perhaps the most dynamic in Africa and Nigerians are known to be merchants and entrepreneurs (VERY hard working indeed). To demonstrate my point, look at the independent carriers. They are totally ready and capable despite paying exuberant $$$ for insurance and airport/nav fees (not to mention fuel!!).
As for the specific Virgin/Nigeria relationship, it will only fail if the Govt. doesn't move to convince the masses this is the best Nigeria can get for now in its bid to boast a functional national airline. Corruption and other challenges are not impossible to overcome. As proof to my statement, look at MTN (South Africa's) telecom investment in Nigeria. MTN just recorded millions of dollars in profit.
Nigeria Airways' ex-staff: They can all face reality, they were not even showing up at work. Practically, Nigeria Airways died many years ago. In recent times it operated as a glorified travel agency, wet leasing from whatever airline it could RIP off (refer to the Air Atlanta saga, or New York route in SAA partnership where the latter threw about 60 seats to Nigeria Airways, we are talking 747-300 capacity here).
In conclusion, I think that most of the people behind the opposition to this deal are out to protect their own interest and not that of the country. If given the chance, Virgin Nigeria can succeed, and formidably.
If there is a will, there is a way