You can take the person out of the city, but can you take the city out of the person? One of the problems with living in Manhattan is starting to think that it’s just like the rest of the world and then abruptly finding that it’s not. You can get the best of everything in New York, and it is possible that your neighborhood butcher was an exceptional one, even by New York standards. It may also be that the beef you got in New York was aged, which benefits both the texture and flavor of the meat, and is perhaps not available near you now.
We put your question to the helpful folks at the National Cattlemen's Beef Association and basically got the same answer: "You are right that Manhattan is fortunate to have many of the best butchers around and they pride themselves on super high-quality meat. It is unlikely you'll find tons of other butchers outside of New York City that have the same quality, but they do exist."
The association folks suggest you have a heart-to-heart talk with a local butcher to verify that the beef you’re buying is indeed graded prime. Prime beef is generally not available at grocery stores and not even every butcher or specialty food store carries it. The association also suggests that someone at the Florida Beef Council may be able to steer you to local butchers that have Prime beef available.
Finally, they ask, have you considered ordering your filets from a New York establishment such as Dean and Deluca?
And oil and garlic do not tenderize meat, they just add flavor. Most commercial tenderizers contain papain, a derivative of the papaya. But, frankly, if you need to tenderize a filet mignon, you should be shopping elsewhere.