What is entailed for someone who intended to enter a state of ihram from Medina, then was compelled to enter Mecca from Jeddah without ihram? Is a fidyah obligatory upon him, and how can it be paid from the United States of America?

If you arrived in Jeddah without ihram, intending to go to Madinah first and then assume ihram from there, but were prevented from going to Madinah, and thus assumed ihram from Jeddah, then there is no harm upon you. You did not intend Hajj upon your arrival in Jeddah, so you were not obligated to assume ihram from the miqat. Rather, you intended to perform Hajj from Madinah. Since travel to Madinah became impossible, you assumed ihram from your location (Jeddah), which is what you did, and nothing is binding upon you.