I voted even though the premise of the question is that they are breaking the law, and whether or not they should be charged.
They are not breaking the law.
You are pointing out the code and seem to be stating that they are breaking the law. So, I would like for you to describe why you think they are breaking the law, and some legal ruling to back it up.
Has there ever been a congress-person (state or Federal) that has been charged with a felony for not being present to start proceedings? I should probably stick with any state congress-persons.