If speaking in the bathroom happens when one is relieving oneself, it is not allowed, and it is contrary to good manners and dignity. As for speaking in the bathroom at a time other than when relieving oneself, there is no text to indicate that it is not allowed.

If the sick person cannot do Wudu with water because he is unable to or because he is afraid that it will make his sickness worse or delay his recovery, then he should do Tayammum. If the sick people cannot stand, then he may pray sitting. If he is unable to pray sitting, he may pray lying on his side. If he is unable to pray on his side, he may pray lying on his back with his feet towards the Qiblah.