The simple part is what was going on in the Mir Yeshiva in NY. Learn Torah and God will do the rest. Don't worry about making a living because when you learn Torah for its own sake God will provide.
That part is the simple unambiguous part.
Then there come the later confusing issues when this structure seems to break down.You get to Israel when people "talk the talk" about trust, but in fact spend all their time and effort trying to get charity from rich secular Jews and the State of Israel and then call that "trust in God". Hypocrisy at the highest level.
Then you get to kollel's in the USA when they don't even bother to "talk the talk." There it is all about using "supporting Torah" as if they are geniuses at the RAND Corporation Think Tank, and are getting paid for their work and services.
To add to the confusion is the history itself of Navardok which made trust their central meme and theme.
This is a statement of the basic ambiguity that surrounds this issue. The difference between what the Torah says and what people do. People that present themselves as authorities in Torah that are insincere, scum bags that darken the name of Torah.
See Cult behavior:
Kollels certainly are cults.
You are not supposed to make a living by learning Torah, nor teaching it. And you are not supposed to ask for charity because you are learning Torah. [See the Mordechai in Bava Batra dealing with the problem of even having teachers for children!!! I kid you not. מה אני בחינם אף אתם בחינם
Being unscrupulous is a trait of kollels. Lying to get money.
But the issue still remains how to come to authentic trust in God and to learn and keep Torah for real?
The trouble that I see is very rarely is any religious group anything but a cult. So to be Kosher Yid one really just has to learn Torah on one's own and give up the idea of being part of any group.
My suggestion is to support the places that I recognize as being "LeShem Shamaim" לשם שמים --for the sake of Heaven. I mean there are a few yeshivas that I was very impressed with that I thought were teaching people good values. Those are the Litvak Yeshivas in NY. Chaim Berlin Mir Torah Vedaat Shar Yashuv. I know little about Ponovitch in Israel, but just seeing the book Avi Ezri of Rav Shach shows me that that place must be the Mount Everest of the Torah world.