When politicians talk about putting their assets in a trust, they're usually referring to a "blind trust" that's managed by somebody not close to the politician, and where the assets within it aren't visible to the politician (so they can't knowingly make policy that enriches themselves). Better politicians would liquidate their original assets first, so all they put into the trust is cash.
That's not what Trump did. Trump put his original assets into a trust run by his son and CFO. He knew what assets were in there and, even though he allegedly didn't have control over them, he did wield influence over the people managing them.
Hotels keep these records. I'm not going to dig it up now, but I believe the law states that federal officials have to disclose income received from foreign sources (including through legitimate business dealings) and IIRC, Trump's businesses have disclosed that revenue.
