ok so to give you an um ackshually here.
Technically if we were to develop a real general artificial general intelligence, it would be limited to the amount of knowledge that it has, but so is any given human. And it's advantage would still be scale of operations compared to a human, since it can realistically operate on all known theoretical and practical information, where as for a human that's simply not possible.
Though presumably, it would also be influenced by AI posting that we already have now, to some degree, the question is how it responds to that, and how well it can determine the difference between that and real human posting.
the reason why hallucinations are such a big problem currently is simply due to the fact that it's literally a predictive text model, it doesn't know anything. That simply wouldn't be true for a general artificial intelligence. Not that it couldn't hallucinate, but it wouldn't hallucinate to the same degree, and possibly with greater motives in mind.
A lot of the reason human biology tends to obfuscate certain things is simply due to the way it's evolved, as well as it's potential advantages in our life. The reason we can't see our blindspots is due to the fact that it would be much more difficult to process things otherwise. It's the same reason our eyesight is flipped as well. It's the same reason pain is interpreted the way that it is.
a big mistake you are making here is stating that it must be fed information that it knows to be true, this is not inherently true. You can train a model on all of the wrong things to do, as long it has the capability to understand this, it shouldn't be a problem.
For predictive models? This is probably the case, but you can also poison the well so to speak, when it comes to those even.