An old-fashioned way to say "no."

Got some help from the FB group 日本語, understanding this panel from 大東京ビンボ―生活マニュアル. They say drop the -u at the end of a verb; replace with -a and add ず, and you have an old-fashioned but still used way of saying ないで ("don't" or "without...").

I tried all the different verb endings, both -ru and -iru/-eru, plus the two irregulars する and 来る, and Google Translate agrees they mean what's predicted. I'd say we're good.

食べらず。
買あず。帰らず。待たず。書かず。泳がず。死なず。飛ばず。飲まず。話さず。
来らず。しらず。

Fits 彼女's personality: she is competent and polite, and she's at a traditional event, so it makes sense she'd go a little retro in her speech.