Who is Tom Bearden, and why should I care what he has to say? When somebody starts talking about "hyperdimensions", you can already assume he's some kind of crackpot.
To answer your question, stem cells aren't just basic organic matter, they contain DNA in them too. The DNA is in its most undifferentiated state inside the stem cell, the stem cell can be turned into any other cell in the body, at which point the DNA is no longer undifferentiated. The entire DNA genome is still inside all cell's DNA, but the most initial state is lost. Think of the stem cell as a computer soon after its rebooted, and it's lost all of its built-up states and its back to its default state.