Not necessarily. The best theories as to how the Rossi and Fleichman-Pons experiments/devices produce anomalous heat involve not fusion, but transmutation of the metal into another metal: the metal isn’t catalyzing fusion, it’s what’s undergoing a nuclear reaction. (In the case of Rossi, nickel is transmuted into copper, releasing energy.)
Rossi denied last September that the key reaction was nickel changing into copper. He said that may happen in small quantities, but this is not the primary source of excess energy.