The monitor overseeing the Trump Organization during the civil fraud suit brought by New York Attorney General Letitia James has uncovered a mysterious loan that could unravel Trump’s legal position, wrote law expert Lisa Rubin for MSNBC’s MaddowBlog on Wednesday. James is alleging in the suit that Trump and his two adult sons have systematically misstated the value of their properties to manipulate tax balances and loan interest rates. She is seeking $370 million in fines and the dissolution of the Trump Organization; presiding Judge Arthur Engoron has already partially ruled for her on the m…