Honestly for me, I would rather see an immigrant struggle to say the right words in English with a translator helping him select the right words than here him rattle off some other language. That would at least show he is trying. This guy speaks perfectly good English, IMO, he should have used it. As said above, using a translator is just theater. Showing that he learned the language and intends to use it would get him more respect from me.
My great grandparents spoke German around the house even though they were at least 3rd or 4th generation US citizens. However, they understood that English is the common language in this country and used it outside the home.