Defamation is definitely one problem with this tool. Once there is “evidence”, it can be (ab)used without consequence by someone, because they can simply point at the tool output. If the output is usually “good enough”, it will provide an alibi for their actions: “I didn’t make a mistake, the computer did.”

Nobody who bothers to check what the tool does will be swayed by this. If someone wants to make shit up, and their audience will not bother to spend 30 seconds looking at their "sources", they could just write a script that outputs whatever they wanted and then point at that script.

You are putting a lot of faith in people to do that diligence. Most people will take the “evidence” at face value. And yes, people do write scripts to generate material to defame or hurt others.

You're making my point. People take evidence at face value, so a program like Maigret makes no difference. Why bother using Maigret when you can just make stuff up?