While using the Venus return chart of that time period sounds like an interesting idea, it sounds like a lot of effort for information that could be obtained much more quickly with just the horary asked. Horary questions on the truth of a report or rumor are pretty common and fairly straightforward.
That being said, this person would be represented by Mercury in Pisces in the first, and that sounds like a game over right there. I can't imagine a planet with such little power being all that truthful given the circumstances. Typically to see if rumors are true we look to the third house and its lord, and here we see Venus who is also in detriment and Combust of the Sun, so I don't see a lot of points for honesty on this one. I would say the psychic was off on this one, just based on these few testimonies.