Firstly, I'm not going to assume at this point in time that the fact that a top hair loss researcher, Claire Higgins, is on board means something negative and sinister. I admit that the company could be a for-show-money-grab but it's too early to jump to that conclusion at this point in time. We should keep our eyes for the possibility it might be a scam but it's too early to assume that.
Secondly, Their lawyers know the requirements in regards to the use of UK tech, foreign tech, or both. Like you yourself said, YOU "don't know" how they could use UK tech, but I'm not confident you know all there is to know about that issue. This is tricky stuff even for lawyers who work this stuff. And it sounds implausible to me that the UK would require the tech to come from outside the UK. We in the USA have "The Compassionate Use Program", which allows for use of unapproved medical treatments from within and outside of the USA. I can't imagine why the UK would specifically exclude unapproved treatments from within their own UK. Also, even if you're right there might be ways around that requirement. That's the point to having lawyers.
Thirdly, you don't know that the condition has to be life-threatening in order for use of the Special Program to be approved. If the populace is happy with the treatment I don't think the regulators would shut it down.
My most negative concerns are that they might not raise sufficient capital to stay afloat, they might not be able to get the OK from the owners of the tech, and they might have to charge an exorbitant amount of money for treatments just to pay expenses.