You're not accounting for his Panama and other offshore accounts. There are surely hundreds of millions stashed in various shell companies, plausible deniability allowing, that are owned indirectly by Trump but not in his name. His problems will be more to do with laundering than less about having money. Paul Manafort struggled with this and his small brain got him caught. Trump has many pieces of apparatus that allow him to bring dark money into the US cleanly. Watch for property resale deals at 2x market value, for example.