This is from their linked in page:
“Since its inception the company has developed into Australia's largest and leading provider of live performance based statistical information and diversified into a range of vertically and horizontally aligned services including the provision of television graphics, internet and wireless products, publishing and other related broadcast and media services. Champion Data is the official statistics provider to the AFL, and have significantly broadened our content base and now provide services to all major Australian sports including NRL, Rugby Union, Cricket, Football and Netball.”
So they’re certainly not the official provider but you might be right that they provide services for individual teams. That would make sense because it’s not the NRL’s job to provide clubs with specific data sets they require. However, this in no way makes them more accurate than NRL stats. NRL Stats are the official stats for the NRL.
https://au.linkedin.com/company/champion-data