The thing is, you're looking for or think you "need" a mentor. Esp. thinking it has to be someone in finance or banking.
While all that might actually be true, you make your success and advancement dependent on others and narrowing your field of possibilities. You might find a mentor at an art exhibition or a self-improvement seminar or a fishinhg trip. Who knows. It's mostly the personal level where it's going to click. Business comes later.
And that fixation on a mentor is what people can "smell" since there's a huge risk in coming across somehow "needy" and your actions are guided towards a mentorship and not a personal relationship. Mentors don't look for people who are obviously looking for mentors, because those are often the type of persons that are looking for a guru/master even if they wouldn't call it like that.
The "gems" are quite often those simply following their own path and doing what they love, no matter if they are overly successful with it moneywise or not.
There's an old saying: "The teacher will show when the student is ready". Might sound cheesy, but fuck, that's how I experienced it every single time myself and with others.
Sometimes people might know each others for years without any closer interactions, or have been in the same circle of friends since ever but never met. And suddenly, all pieces fall into place.
Everyone I found, I bumped into at the bar with a beer in my hand, after seminars that go over days sometimes weeks, by accident. Or by simply doing my hobbies and making contact with like-minded people. Suddenly there was a hedge-fund manager sitting next to me at an Amsterdam coffeeshop wearing sweat pants, where we first talked about our love for import hash for 2 hours before we even came to the idea of mentioning our jobs i.e.
You know, they are people too with human needs and habits... ;)
Regarding alternative finances like cryptos, yes, mainstream banking is most likely the worst sector to look for. For them, cryptos are the devil, stuff for "consipracy nuts" (their words not mine) or a competition that would make them useless over night... A nice playground at best.
So you might want to look at "fringe" economics (again, not my words) like Austrian school of economics for example or the "New Austrians" around Prof. Fekete like http://nasoe.chayns.net/aboutus?id=93 just to give some examples. Some of the most interesting people in the field I ever met.
Generally speaking, every sector has its "fringe" areas that are always a good starting point, since being a bit on the edge of a community, being smiled at by your colleagues for your strange interests etc welds those people together in a "we against the world" kind of way. Simple group dynamics and that's where the spark for passion and inner fire comes from. Not from the fields where every arbitrary college student with blinders left and right tries to make a standard career and is just out there trying to find an investor.
Or you might wanna talk with your strange professor at college whom no-one else might notice and you'll find a great area of research with fascinating possibilities for your master-thesis.
Basically, get to know people outside of mainstream. Great ideas basically never came from those thinking inside the box who are trapped in the system and hamster-wheel. And hell yes, that's though and you will be confronted by a lot of resistance by those trying to keep you within. Friends, familiy,...
But again, if you go there to find a mentor, they will most likely not care since they are confronted with that by the hundreds since everyone tries to do that. It has to be you interest in the topics they put their heart into and even then there's no guarantee.