More on these alkali rydberg clusters! I don't see much on that.
An extended discussion is probably worth a separate thread, but I think its apparent transmutation effect on materials it comes in contact with might be more related to its extreme properties as very low density condensed matter, at least when in highly excited form. While in those experiments a work function of <0.7 eV was measured, from theory it could get down to 0.1 eV or less. The thermionic current density of surfaces with such work function could be enormous even at room temperature, in the order of 1 megaampere/cm2.
Other strange effects and changes in the affected materials would also likely occur. For example, their tendency to lose electrons could become so high that they might not be able to remain bonded together and may turn into plasma or slowly evaporate at room temperature, or become extremely reactive.
I don't think all of this would be usually observed however, as after formation alkali Rydberg matter clusters will spontaneously de-excite to energy levels where several of their properties will be much less exaggerated.