Because... the field for experimental vaccines is crowded. The anti viral drugs of NanoViricides promise the first CURES for viral disease.
NanoViricides is attempting to change the paradigm for the treatment of viral disease in much the same way Penicillin changed the paradigm for treatment of bacterial disease early last century.
Seems pretty simple, and if successful, extremely lucrative.
Why do we bother what? You want to be more specific with your question?
"Why do we bother" with H5N1? Because Sanofi's vaccine is already less effective than it would have been 6 months ago when they first began raming up production.
"Why do we bother" continuing H5N1 since Sanofi is getting the money? Because $192 million is only a part of what was appropriated, and not even the majority of the total appropriation.
"Why do we bother" some other incomplete thought within the open ended unpunctuated question?