I have a POA for health care for my mother but now the hospital states it is invalid as witnessed by two of her other children witnessed it. This is apparently not legal in WI. In addition, she has been declared incapacitated by her MD. How are we to get a new POA if she is incapacitated and not able to know what she is signing?
If it doesn't say this, you used the wrong form. At this point you will have to pursue Guardian/Conservator status via petition to the court.
That seems like a very peculiar law, if it is in fact a law. Have you researched it online?
What does the hospital want you to do now? My mother never signed a POA. The hospital just wanted someone, anyone, to be responsible for her. Who we picked among ourselves didn't matter to them.