What has been overlooked is the fact that Reb Eliyahu Bal Shem actually lived in Prague at one point. The legend of the Golem is quite old and moved around, but originally not by Jews.
Perhaps, the news went out about Reb Eliyahu Bal Shem’s Golem in Prague, but spread to people who haven’t heard of him. They associated it with the more families mystical rabbi of Prague.