Contradicting to this theory, there was a different theory that "chin" was a variant character of "chin" (rare) and Wado-kaichin was read as Wado-kaichin causing a dispute for over 150 years since the Edo period.
それに対し、「珎」は「珍」の異体字であり、和同開珎は「わどうかいちん」と読むという説もあり、江戸時代から150年以上論争が続いてきた。