>>50mg of a solution is different from 50mg of iodine. Way different.
He was referring to 50 mg of Lugols solution - 5% iodine, 10% potassium iodide,85% distilled water - yielding 6.25 mg per horizontal drop -- and/or Iodoral, which contains 20mg iodine, 30mg potassium Iodide (the 50 mg per tablet) in a colloidal silica base.
50 mg of either product is a standard therapeutic dose.