The boring context is that, in situations like this, the plaintiffs will indicate a large(ish) batch of defendants that will gradually slim down as the case moves forward in the court - the plaintiff attorney has a duty to cover all possibilities.

Some of the other comments here already touch on who may be the more liable party other than Google. The public works department seemed to have played a game of passing around the 'accountability ball' which contributed to a tragic event.

These cases generally take a pretttty long time to come to actually come to a close and it's an absolutely surreal and bleak experience the entire time.