I do find evidence of registration on Companies House's register. I note that it was only registered on May 19, 2021. Scammers can and often do register fraudulent companies. It gives the illusion of legitimacy and, then, when the time comes for them to file their tax reports, they don't, eventually become inactive and ultimately get struck from the register. By then, however, the damage has been done and many people have believed them legitimate.
The fact of their registration is inconclusive. It's too early to rely on it, though in and of itself it is a good sign.
On the other hand, they are a financial firm and it is significant that they have not submitted themselves to FCA regulation. They are not listed on your FCA register under either the name of Commodity Trading Company or Treasure Reef Group.
The US does have a company called Treasure Reef Group listed on the website of the National Futures Association, but it is a non-member. Additionally, there is no address for it so it's impossible to say if this is the same UK firm or some other business by that name.
The website for TRG is exactly 67 days old and, oddly enough, the IP address traces to Tokyo. That's irregular and suspicious given everything else, though certainly not illegal.
I cannot confirm that this is a scam. It's simply too new to do that. But if it's not authorized to trade in your country, it's a fair bet that your friend will be defrauded. Almost 100% of all unregulated financial firms are outright frauds. I am leaning in the direction that your friend is going to lose his money.
One hallmark is that the sites tend to be brand new and are set up to disappear quickly. This one conforms in that regard. It is 2 months old and set up to disappear by its first birthday in May. That's the least amount of time you can register a domain name for. A short-lived site like this is always highly suspicious and the sign of an almost certain scam.
Another hallmark is that they make it very attractive and easy to put money in. They typically require only a small opening investment and they show you how very quickly your money is supposedly growing. They may even let you test the waters and withdraw something. But then they turn your account over to an agent who induces you to make much heavier investments. Once you do, that's the last you'll see of that money. They find one way after another, after another, after another to keep you from getting your money out.
I suggest telling your friend not to think in terms of investing any more money without first getting some of his earnings out. If they give him a runaround with multiple withdrawal fees which accomplish nothing and demands for sensitive personal information, he's hitched his wagon to a fraud.