She [topic-は] everything acknowledgment says-as-if I [to-に] winked.
万事承知と言わんばかりに — 言わんばかりに is a literary expression meaning 'as if about to say.' 万事承知 (ばんじしょうち, 'I understand everything') is a formal set phrase. 目くばせする ('to give a meaningful look/wink') is a compound suru-verb.