Nulls Brawl Over Brawl Stars – Is It Cool or Risky?

Hi, I'm playing Nulls Brawl instead of the official Brawl Stars. I downloaded it from a third-party official source https://nulls-brawls.de/, and I've been enjoying it for the past 6 months with no issues. Is it okay to keep using Nulls Brawl, or should I be concerned about anything? I'd appreciate your suggestions.