@stevenebraun, how was Sense “explicitly told” that those two detections were the Dishwasher ? I think you’re misperceiving what happened. Those two detections, of Heat 1 and Motor 1 were native detections, completely independent of the dishwasher monitoring via the Kasa Smart plug. More on how native detections are done, here.
If the the two new native detections pretty much reliably cover all the power usage you see from your smart plug, you can merge the two detections and transfer your Kasa plug on the dishwasher to another device. Please note that the past history of the Dishwasher will stick with that smart plug device, even after you have it attached to something new.
If the two components, Motor 1 and Heat 1 don’t completely cover all of the behavior you observe from the Kasa plug, you can tell the smart plug device that those two detections are part of the existing Kasa-measured dishwasher to avoid double counting.