IIRC Putterman’s group (and a few others) thought they had seen excess neutrons (the kind that indicate D-T fusion reaction is occurring), but they could never conclusively prove it was not coming from the natural background or calibration sources.
According to the Wikipedia:
In February 2005 the documentary series Horizon commissioned two leading sonoluminescence researchers, Seth Putterman[9] and Kenneth S. Suslick, to reproduce [Rusi] Taleyarkhan's work. Using similar acoustic parameters, deuterated acetone, similar bubble nucleation, and a much more sophisticated neutron detection device, the researchers could find no evidence of a fusion reaction.[10][11]
Subsequently, Taleyarkhan was sanctioned for scientific fraud in connection with his bubble fusion "results".