It is doubtful Chlorine Dioxide displaces Iodine as Chlorine does.
For example table salt sodium Chloride NaCl has a Chlorine atom combined with a Sodium atom but you can't live without it. The Chlorine is tied up to a Sodium atom.
Chlorine Dioxide ClO2 is not the same as Chlorine Cl2. As I understand it, Chlorine Dioxide breaks down in the Human body forming substances like table salt , water carbon dioxide, and other harmless substances. Chlorine Dioxide simply doesn't break down into free Chlorine. They smell similar but they are not the same.