I have no idea who Does 1-50 are, so that is something I would want to know, but it means that many other people and/or entities were sued.

Netflix could be sued in this case, because they are the distributor of the miniseries, hence making them potentially liable, and have deeper pockets than the LLC that produced it. Each production also carries what is known as E&O (Errors and Omissions) insurance. Let's say someone was physically hurt during the filming of the miniseries. In that case, the LLC would be sued and be liable, but you ALWAYS sue everyone you can name (hence Does 1-50 in the Netflix case), especially a party with the deepest pockets, such as Netflix.

Although the court did not dismiss the case outright, it doesn't mean that Netflix would necessarily have lost, it just means that Netflix determined that settling would be more advantageous than an expensive, prolonged lawsuit. I have worked for several companies (Red Bull, Amazon) who don't want to deal with lawsuits and will just settle things under a certain dollar amount if they can.