This is pretty big. Moving the detectors and getting a proper inverse square law diminishment in the neutron flux density of appropriate magnitude is somewhat incontrovertible.
Personally, as a soi dissant physicist ( nonpracticing Ph.D. , ) I find the proposed mechanism ridiculous. Consider that the center of the sun is at 10 million Kelvin, and is a very poor producer of fusion, which makes sense when you realize it lasts billions of years without burning out. The human body generates more heat per unit mass than the sun.
There are various superlatives to illustrate the extremity of the solar center environment: A pinhead maintained at that temperature would kill a man a mile away with its radiation ( my uncle told me that years ago - never verified it. ) The radiation pressure alone ( i.e. light pressure, which requires extreme conditions even to be detectable ) would explode the earth ( my calculation . )
Also, perhaps more significantly, note that the hydrogen at the solar center is compressed to 50 times the density of water. Solar collpase is being resisted by the degeneracy pressure of the electrons, which are no longer orbiting the protons, but whizzing about in a background "sea" of negative charge. The protons behave as an ideal gas against this background, mostly "colliding" and being repelled by their coulomb repulsion. Only very, very, occasionally do they have the required energy to approach within the fusion reaction cross section.
The bubble rationale has it that the energy is "focused" and nonthermal, but it has to be thermal, or become thermal very quickly, so my judgment is that the bubble collapses will fall many orders of magnitude short of providing the kinetic energy to fuse protons or deuterons. Obviously, the proponents argue otherwise.
From an experimental point of view, we have this: "In the new setup, the researchers dissolved natural uranium in the solution, which produces bubbles through radioactive decay."
What kind of decay did you say? Producing what particles?
Also note the claim that the neutron radiation is a "statistically significant" increase over background. This is the mantra of ESP researchers.
As to the inverse square verification, I would ask how they could verify this if there signal is much smaller than background, as implied by its relegation to the realm of the "statistically significant".
Anyway, just MHO.