Re: Liability
From starting the research to vaccinating everyone is going to take, best case scenario, about 2 years. That's with two doses. For one dose, maybe you could do it in 18 months. That is using venues which would normally be used for other things. Not a problem in the case of coronavirus, because those other things can't restart until everyone is vaccinated anyway, but it would be a problem for a flu vaccine deployment.
Even so, 18 months is way too long for a successful flu vaccine deployment; so that's why I'm not sure it is viable.