Meaning of "one that is now reliant on public appeal for help is to be a breakthrough"

Question

There is one more sentence in this video. Source is : https://youtu.be/3prCCJIhIKA?t=145

This is original sentence - one that is now reliant on public appeal for help is to be a breakthrough

I could rewrite it in simple speech like this but no understanding at all in terms of what it says -

one that is now dependent on making a serious request to public is to be a dramatic turn in an incident.

but what is its meaning?

Answer 1

Firstly, that isn't a complete sentence, but a fragment which follows a reference to "the case" (of the disappearance of Madeleine McCann).

Second, you've misheard it: it is

one that's now reliant on a public appeal for help if there's to be a breakthrough.