Also what if Tanavast is the reason Syl slept for so many years. Maybe his replacement revolves around her, whether he knew it was specifically Kaladin or not. Maybe he prepared Syl for his replacement. He didn’t make Syl, the stormfather did, but he was still alive when he had the stormfather begin creating honor spren. Maybe he prepared her just as he prepared the visions for the stormfather to give to someone of his choosing at the appropriate time.