What are the nuanced usages of まず?

Question

The following lines of dialogue is spoken by a girl to the narrative character in a book I'm translating.

「普通の人なら、あの状況{じょうきょう}ではまず間違いなくパニックになるわ。

自分の置かれた状況を把握{はあく}しようとして、混乱しているうちに殺されていたはずよ。 でもあなたは違った。状況を把握するより先に状況に対処した。 それがあなたの才能なの」

I know まず generally means 'first', but I am unable to parse out what 'first' is denoting in the above line.

Does まず denote a aspect of time, as in 'first (time) in that situation...'. Does it denote a action done by 普通の人 such as 'first they would have panicked...'/'they certainly first would have panicked', etc? Does it denote something else? Or does まず not mean 'first' in the above sentence, and instead mean something along the lines of 'about', 'almost' or 'anyway', as defined on Jisho?

Roughly Translated Context

Answer 1

「普通{ふつう}の人なら、あの​状況 {じょうきょう} ​ではまず間違{まちが}いなくパニックになるわ。」

「まず」, in this context, does not mean "first" as you stated.

In Japanese, it is synonymous to 「おそらく」、「ほぼ」、「多分{たぶん}」. In English, it would be "for the most part", "likely", etc.

Does まず denote a aspect of time, as in 'first (time)' in that situation?

No, not in that context, as I briefly explained above.

Does it denote a action done by 普通の人 such as 'first they would have panicked...'/'they certainly first would have panicked', etc?

Sorry but no. It denotes a (rather high) probability or likelihood in the sentence in question. It does not denote an order of actions taking place. "First" is only one of the meanings of 「まず」.