User blog comment:Zathronas/Analysis by an author: World of Remnant, Kingdoms/@comment-4909254-20140919025130/@comment-24218038-20140919025857

First, let's wait and see Ironwood's reaction to finding Ruby there. You might be surpeised by his reaction.

Second, Even if they were together, that doesn't mean they want to reveal their association. making sure they arenot seen in vacinity to each other ensures that no one puts 2 and 2 together.

Third, they had a third witness there. To keep the secret, Ironwood would haveone of two choice. Attack Ruby and hope she doesn't escape or attack Cinder and hope Ruby buys his acting. Better not put himin this situation. Especially since she was finished anyway.