IP Domain registrant

Sorry for not beeing absolutely sure if this is the right forum to put my request, but as it deals about fraud, and the physical person behind a domain or IP I just take this one. It comes like this.

hm may someone can help me to find out, who the hell registered a domain, a very specific one, that is more than annoying, it comes along with some help from a huge bank, it tells people like my wife that this title is based or down by law, and on the providers-service I can see, there are 271 domains registered to this very specific IP. It is not about malicious code or a botnet, it is about making money for nothing or quite a profit telling to be an official entity based on a certain law.
After running nmap, tracerout, whois and more, I just got the information about the provider or hoster of this domain.

AcEb.org.br - Ac Eb

trying this tells me to get the whole report for just 50 bucks. Is there a better way to find out who is behind that fraud of this specific domain? I would just like to get the maintainer, programmer or registrar for that. The way back archive did not help either.
Any help or clues are welcomed, thanks in advance.