Yuji Naka said in a interview that it is probably the same prototype stolen in New York in 1992.
We say rediscovered because the existence of the proto was already known, and Simon Wai himself played it in 1992. The prototype was initially rediscovered in December 1998, when Simon Wai released on a newsgroup a beta version of Sonic 2 previously found on a Chinese website. More interesting for our site, the beta of Sonic 2 is currently the most important beta document of the series, and one of the most intriguing ever. Released in November 1992, after the great success of the first episode, the new Sega title become promptly the best selling game for the 16 bit console. Sonic 2, like the other installments of the series for the Genesis ,doesn’t need any presentation.