Following are a number of back-translations as well as a sample translation for translators of Isaiah 49:23:

• Kupsabiny: “Kings/rulers shall guard your children like fathers
  and the wives of rulers shall nurse (them) as if they were the mothers.
  Those kings shall bend in front of you to honor you
  and wipe the dust off your feet.
  That is when you shall know that I am God,
  and those who trust in me shall not be disappointed.” (Source: Kupsabiny Back Translation)
• Newari: “The kings will be like your father
  and their queens will be like [your] care-giving mother.
  They will come and lie prostrate on the ground before you.
  They will lick up the dust of your feet.
  Then you will realize that I am the LORD.
  Those who put their hope in me will not fall into shame."” (Source: Newari Back Translation)
• Hiligaynon: “The kings and queens will-serve you (sing.); they will-take-care of you (sing.). They will-kneel to you (sing.) as a respect, and they will- surely -caused-(themselves)-to-be-under- your (sing.) -jurisdiction. Then you (sing.) will-know that I am the LORD, and the ones-who-trust on me will- surely not -be-disappointed.’” (Source: Hiligaynon Back Translation)
• English: “Kings will serve you and will tutor/teach your children,
  and their queens will take care of your young children.
  They will prostrate themselves in front of you
  and humble themselves by licking the dust off your feet.
  When that happens, you will know that I, Yahweh, have the power to do what I say that I will do;
  and those who trust in me will never be disappointed.’” (Source: Translation for Translators)