Complex sentence: Returning to Morton's farm, K finds a hidden date that matches a childhood memory about hiding a toy horse, which he later finds at an orphanage, suggesting that his memories--which he thought were implants--are real.
Split into simpler sentences: Returning to Morton's farm, K finds a hidden date that matches a childhood memory about hiding a toy horse. K later finds the toy horse at an orphanage, suggesting that his memories--which he thought were implants--are real.