interesting, and even as Eliahu was chief rabbi (sic!) of Chelm, this does not sound like a joke!
He lived a short life born after and died before Maharal, there is 1630 book assigning Golem and “old synagogue” stories to him. Chacham Tzvi, Yaakov Emden are his descendants.
I don’t see references to him being in Prague, but I also don’t see references that he was not (sorry for using Chelm style!)
For further confusion, there was another Eliyahu Bal Shem _Loanz_ who was born at a similar time and actually was Maharal’s student. So, maybe this is how golem was transferred – through confused references to two Bal Shems?