Shaking their head, Soldat says, "It was the memory. There were rocks, and when you touched them, you saw a memory. Yours, someone else's. I found his. He and his brother were arguing about how to deal with the plague victims."

They pause, and add, much more cautiously, "And you were his brother. Right?" They probably mean "are", but in the context of the memory, and how Ardyn does seem kinda... different now.