sounds fake, more if comming to a brazilian server... you know.. pretty much competition on brazil on emulated servers, other servers try to shut down competence to get new players.
Also, you shouldnt use the NCZ0ft trademark names or images on any of your sites, not even hosting the client of files... that is just asking to get punched on your face.
Btw, NCZ0ft doesnt own L2j on any way, so you dont need any authorisation to run L2j on your server, because L2j is not Lineage.
Remove trademarks and images, tell ur hosting that real infringing content was removed. They will try to reply to the email and never get a response. Also an email is not a legal way to send a Cease and Desist order, tell them to verify the authenticity of the email, since it could be a fake.
There are several L2j servers hosted in USA where they can shut them down in a blink of an eye, and they have never done it... there is no reason to shut down a more distant server out of their reach on Brasil, and if im not wrong the official parter of NCZ0ft in brazil is Level Up! Games Interactive Brazil.