Changing a patient’s name

My friend has cancer and is at a stage where proven medicine no longer has any solutions. The friend is not religious and he asked me about changing (adding) his name. From browsing Google I saw 2 options:
The traditional approach – there is a tradition of changing the patient’s name and adding Chai or Haim or Raphael – for example, in Rabbi Ronen Lubitz’s reply.
The mystical path – you need to find someone who is an expert in the mystical side of names – who will examine the name and see how to change it in the optimal way. In this path, I would be afraid of charlatans, and the only name that jumped out at me that I think (maybe because of his father) is not a charlatan is Rabbi Shmuel Eliyahu – although there are probably greater ones than him in Kabbalah.
It seems to me that one should choose a path according to the inclination of the heart/mind, and if there is no such inclination, through logical thinking – if there is meaning or benefit in this, it is better to choose the mystical path, which essentially also includes the traditional path.
Does that make sense?