(a) Ni does not form such Rydberg matter except in v low density form at v low temperatures.
In nature, these exotic crystals can be formed in many ways by many elements and compounds and at high temperatures in cooling plasma. Just because science uses cold temperature methods to study this stuff does not mean that nature does not find its own ways to make this material in many temperature regimes.
For example, there is a reputable theory that postulates that the red-orange plasma afterglow of a lightning bolt called ball lightning is Rydberg matter.
I believe that some forms of Rydberg hydrogen or H-O is produced by the extreme high pressures and temperatures occurring during cavatation. The intense ultraviolet radiation coming at or very near the end of bubble collapse in sonoluminescence is a clue that highly excited hydrogen gas is being generated.
As background, the Hydrogen atom can have a principal quantum number that ranges from 1 (the ground state) to 137 (infinity).
Highly excited molecular dissociated atomic Hydrogen atoms are called Rydberg atoms with one electron in a circular orbit having a very high principal quantum number.
These closely spaced far out high energy Rydberg states form what is commonly referred to as the Rydberg series.
High energy ultra violet waves are formed when an electron in an extreme Rydberg orbit falls all the way down to the low energy orbit close to the ground state.
The difference in the principal quantum number between the initial high energy state and the low energy final state defines the wavelength in the emitted photon.
When this principal quantum number difference is large and the orbital fall of the electron is great, the emitted photon is highly energetic and is found in the deep ultra violet wavelengths.
The presence of ultra violet photons from hydrogen spectral emissions is a sure indicator that a Rydberg atom was involved in this energetic reaction.
Any cooling plasma of hydrogen or other elements having an outer single s-orbital electron will produce Rydberg atoms.
Cavatation is extremely powerful. It can produce 5 nanometer diamonds from graphite feedstock in a few nanoseconds, it is likely that as the plasma produce by bubble collapse cools, Rydberg atoms form from the plasma.
In Rydberg material, the strength of the dipole field goes as the 7th power of the principle quantum number. In a nano-crystal of a 1000 atoms the dipole field is produced COHERENTLY as if by a single super atom.
These crystals have been produced experimentally up to 2000 atoms strong.
See
http://arxiv.org/pdf/1103.2096v2.pdf

A Rydberg Crystal
(b) the large dipole moments do not result in super-large electric fields such as would be needed to create nuclear-level energy electrons a la WL theory or mask the Coulomb barrier.
This is why the Nanospire experiments are important. They show that such exotic forms of matter exist at high temperatures and do exhibit strong dipole fields.
Mark LeClair has stated this in support of his fusion claims:
I would like to set the record straight and say that Steven Krivit, up to this point, was highly supportive of my discoveries. I’m surprised and disappointed that he would say that I was careless about the use of the word fusion. Steven allowed me to legally record the three hour long interview he had with me. In it, he repeatedly states his belief that I really accomplished what I claim, igniting fusion in ordinary water, with no heavy water or palladium required. As a highly accomplished fluid dynamicist who worked in the prestiguous Lockheed Missiles and Space Fluid Dynamics Group, I’m not afraid to say that my knowledge of physics and mathematics rivals anyone else in the field. At the tail end of the interview, Steven exclaims, “You did it, your really #%@ing did it!!!” We have been under attack from all quarters from those seeking to dicredit us and spread disinformation.
I will be glad to provide relevant excerpts from the transcript to protect my reputation and a full description of our work to a serious journalist, willing to showcase the tremendous discoveries I have made. Unlike Focardi and Rossi, I am willing to disclose all the details, so that it will be eventually understood and allow people to make up their own minds. I feel Steven Krivit owes me (and Serge) an apology for making such a pointless and untrue remark. I have complete confidence that the truth about the LeClair Effect will become known with time. We have the courage and the knowledge to stand up against all the detractors. We will never give up the fight.
Mark LeClair,
Nanospire