To give it my own TL,
"Good Lord! How you/he/she escaped all the way to this remote place!"
Why is と even used there? And what's with は?
It is 「とは」 that we should be looking at here.
「～～～とは」 expresses the speaker's surprise, anger, excitement, etc. The important thing is that one can end a sentence with this 「とは」 without directly stating how one feels about an event/situation. The sentence in question is actually an example of this. The 「ねエ」 ending does not count as a meaningful statement. How the speaker feels is left unsaid. Thus, the 「・・・」 at the end.
Is it like ending-particle わ?
No, it is nothing like 「わ」. To end a sentence with 「わ」, you need to make a meaningful statement first and then, you add a 「わ」 at the end.
why is there used passive form of なる (なられる)?
That is not the passive voice; It is the honorific speech. The speaker is being respectful to the person who ran away.