could this not also translate as "the man is witty but the leader is not" ?
To avoid ambiguity, personally I would probably say "Vala udrimmi issa, yn jentys daor" to mean "The man is witty, but the leader is not" and "Vala udrimmi issa, yn ziry jentys iksos daor" for "The man is witty but he is not a leader"
Same question. Is this sentence missing the word "he"?