The injection region of the stomach below the 'belly button' is also used when some forms of 'blood cleansing' procedures are used with failing kidneys. I'm not clear on this; I'll ping Dr. Beverly ...
I'm way out of my league here - and there's no real information in the article. Bone marrow transplants are given by IV and look like thinned blood transfusions. They used to stink to high heaven because of the preservation chemicals. But, I haven't been near a stem cell or bone marrow transplant since 1993.
I've read about stem cell transplants into veins and tissues in research animals. I've even read about neural stem cells given by IV that go past the blood-brain barrier and migrate to the right site where they're needed.
I'm afraid that the doc is either making the protocol up as he goes along or something worse.