I wouldn't expect Namecheap, a low cost registrar with "cheap" in its name, to have the legal resources to investigate or make a conclusion for each accusation that comes their way for one of their 10 million domain names.
As with everything internet related, I think there's a vast misunderstanding of scale, and difficulty in automation (domains sniping!), for what they're facing.
I also wouldn't expect them to hand out information to anyone that asks for it, especially a large company known for misusing any information they can get their hands on, without a subpoena.
I think the real solution would have to come from a third party group(s) that could collect, monitor, and produce high quality reports, with a high level of accuracy, that all of these registrars could use. Who would fund these groups? Probably whomever gains/loses less from the phishing scams being terminated.