I find it interesting though that they only say that liquid anti-biotics degrade over time. A friend of mine is a pharmacological research doctor at John's Hopkins (I see you include one link to JH) and I asked him about the stability of anti-biotic pills. He said they do degrade and I could expect to still receive the negative effects that normally come with anti-biotics and little or none of the intended positive effects.
I had specifically asked him about Penicillin V, Amoxycillin and Ampicillin that I have which is over ten years past the expiration date. This is his and his wife's specialty and has been for about two decades or more.
Taking expired antibiotics is a great way to destroy your kidneys and liver, throw them out, immediately ....