Yeah, the article confuses a lot of physics and doesn't make sense from a wavelength standpoint. Of course, light has similar properties than electromagnetic waves, but sound definitely doesn't have anything to do other than it can be described with wavelengths.
If you approach the terahertz spectrum, however, resonance is getting a little complicated because it can hit the natural vibrations of molecules. I guess that's what the author was trying to write about in terms of potential medical/scanning applications.
As moving molecules physically in order to create terahertz frequencies seems unfeasible (as of now, u know, because lack of vacuum to make it possible), the only possibility is to generate electromagnetic frequencies and/or light based emissions.
Electromagnetic frequencies for transmission on that scale get complicated real fast though, due to interference and basically everything making it worse, from humidity to infrared waves until basically all longer molecules.
Finding a molecule to use this as a transmission medium in something like a chip as a circuit is a whole other question.
Overall I think the article tries to make "this is ohmagerd" point without understanding the basic physical interactions, laws and properties.