Following are a number of back-translations as well as a sample translation for translators of Isaiah 6:10:

• Kupsabiny: “Because these people have dried heads (are stubborn),
  those people have deafened the ears
  and closed the eyes.
  If it had not been like that,
  (they) would have seen with their eyes,
  (they) would have listened with their ears
  and would have understood with their heads and turned themselves around
  and I would have healed them.’” (Source: Kupsabiny Back Translation)
• Newari: “Then he said to me,
  "Harden the hearts of these people,
  Make their ears deaf,
  Make their eyes blind,
  Otherwise they will see with their eyes,
  hear with their ears,
  and, having heard, will understand,
  and having understood,
  will come back to me for healing.” (Source: Newari Back Translation)
• Hiligaynon: “Then he still said, ‘Cause-to-become-hard the heart of these people. Cause- them -to-be-deaf and blind, for they might see and hear, and might-understand and will-return to me, and they will-be-healed.’” (Source: Hiligaynon Back Translation)
• English: “What you(sg) say will cause these people to become stubborn ;
  it will cause them to not be able to hear what I say and see what I do.
  As a result, they will not see what I want them to see or hear what I want them to hear,
  and they will not understand it,
  and they will not turn to me
  and be saved from being punished.’” (Source: Translation for Translators)