During an interview following his initial reveal, Wylie said the user data his company obtained might be stored in Russia, according to Senator Klobuchar. She asked Zuckerberg if he agrees that that's a possibility.
He responded by saying he had no specific knowledge that would suggest that, and added that Facebook is "committed to completing this full audit and getting to the bottom of what's going on here, so that way we can have more answers to this." The question went unaddressed in the follow-up document as well.
In May, Wylie told Senators in his own hearing, "I can't say definitively, one way or the other, if these data sets did end up in Russia but what I can say is that it would have been very easy to facilitate that."