Not really a fair comparison because food doesn't expire in the same way that drugs do.
Food gets moldy and becomes detrimental to health. Drugs just become less potent... the caveat being that with injectables, there may be some bacterial growth since you don't know where it's been, but it also has the option of being re-sterilized, unlike old eggs.
That being said, I agree the guy is definitely trying to treat OP like a potato: keep him in the dark and feed him bullshit.
No telling how weak it is by now, would not buy.