The humanoid puppet that Sylas gave Elara was specifically designed to be only usable on Earth. The obvious problem with it was that Sylas couldn't Rune craft Will. So to give it life, regardless of how close to a perfect replication of life it was, it needed someone's Will.
Since the humanoid was a perfect—at least mechanical—recreation of his little sister, it thus needed his little sister's Will.
By extension, under usual circumstances, if it was the case that Elara used the puppet under normal conditions, then Elara would be limited by whatever her usual Visualization range was. Or, in other words, whatever range her telekinesis—if she had any—usually was, would be the limit of range at which she could use the puppet.
The fact Sylas wasn't even sure if his little sister had telekinesis or not was probably the crux of this entire problem, but he definitely wasn't thinking about that right now.
