Probably because of the Blackstone purchase of that manga firm. Blackstone has enough money to make a lawsuit literally last forever, I am sure they probably also have many judges in their pocket. Anyone in a legal battle with them will be bankrupt long before the company even has to worry about finances.

Also, Blackstone is connected to BlackRock, and that has all sorts of awful implications for the future of the manga published by the firm now owned by Blackstone.