There is a strong possibility that the interdimensional part is true. Nearly all the native cultures say that it is and why should we be so nieve as to disregard their interpritation.

Rather than to believe these "supernatural" interpritationss by native cultures are merely a primitive way to explain phenonimon they did not understand is niev on our part. In many instances modern science does explain things they didn't understand, in some instances it has never been able to. In those instances the Western culture defines it as folklore or fairytale because of its inability to explain utilizing modern science. Modern science does not have all the answers, as it evolves maybe it will.

In many ways these native, ancient cultures were likely much more close to the truth in many instances than we are today. Partly because the societies did not have preconceived notion, and also because they has direct contact with other intelligence who instructed them, possibly the ones who created them.