The above is a transcript of the interchange between Sessions and Franken
If the last sentence is taken in the context of "those activities", which reference a CNN allegation of an allegation, then "communications" in the last sentence is not a problem, and there is no evidence of lying.
If you take the last sentence out of context, by itself, and extend "communications" to be completely general, then the last statement is incorrect.

I have not seen the full text of the referenced Leahy written testimony, and without that have no informed opinion.