Once again I heartily object to "necessity" as a variable in the development of TP canon. There's no need to know what happened to Annie or Donna like there was no need to know Becky's daughter like there was no need to see ('know' might be a bit of a strong word there
) what happened to Audrey like there was no need to see the Banks investigation like there was no need for Jerry's character to exist at all or to indulge in Coop's breakfasts at the Great Northern.
As a more extreme example, let's consider an anthology series and let's assume we've liked all seasons so far. In this case, there would be - by definition - zero NEED for a further season. But we've liked what they've come up with so far, so why wouldn't we be looking forward to more cool stuff?
] The gathered are known by their faces of stone.