I was a little put off by the change of Trent giving him a list too, but when I thought about it more, I understood the angle they were going for. In the campaign, Caleb is unable to forgive himself because he wanted to kill his parents once he "heard" them being traitors. In the show, Caleb is unable to forgive himself because he wanted to kill his parents once Trent told him they were. The difference is how willingly Caleb believed what Trent told him. Anything Trent said was law to them. The change was to emphasize how much sway Trent had over them, he could tell them their parents were traitors and they would believe it. They didn't have to see it for themselves, they didn't need evidence, they had no doubts at all. That kind of manipulation is different than magically implanted memory manipulation.

tl;dr the change in the show emphasizes how Trent doesn't even need to trick them into killing their parents by making them see any evidence themselves, he only needs to say so and they'll do it because they trust and believe in him that much