Iron Dragon is just a unit. Unless you declare it to be a god.
Actually every unit in the game can be a god, a commander, or a troop, etc. In this case, assigning it as a god to a nation works really well. Anything not unique should work fine.
Im not sure if SemiRand has a CBM version. Id say to expect it to be non-CBM. But Im not sure how much it would break anything anyway as long as no units are used which were created just for use inside CBM.