The reason that Tycho Brahe couldn't leave the banquet to go to the bath room was that the King was present. It wouldn't just have been really rude; it would have been insulting to the majesty if anyone were to stand up before he did.
Regarding Isadora Duncan: How could the driver's attention be "attracted by her cries in the street" when it is also stated that she had been "had been strangled and killed instantly"?