I think the biggest determiner of quality is your skills and vision. So if you need to upgrade, start with yourself first. It is not just a matter of talent and knowledge, but do not discount experience. So putting your hands on a camera, any camera and learning the discipline of going out and shooting. Then there is something I call, learning to read the video, to judge your own work, learning to judge the work of others. Allows you to be critical and understand that your images are created, not found. Understanding the technical is to also understand the relationship between story and image, for example a blurry image might be a terrible image, but a perfect image to tell a story.

I think Guy McLoughlin is giving good advice here, I would advice you to start by buying the book "Rebel without a crew" by director Robert Rodriquez and then view all the 10 min filmschools that he did on youtube. Consider that we no longer use actual film and we have digital recorders instead of cassette and he left out of the book that he had an "IN" in hollywood through his Mom, but for information and basic advice. There is no substitute for experience. When you start making crappy little films of two to ten min long, then you learn to read what you are doing right and wrong. Joining the local film society as Guy recommends, they can watch what you are doing. Much of this is developing discipline, going out the door, give yourself an hour and take 5 min of footage then edit it at home. No substitute for experience, then the youtube tutorials and books will make sense, if you just think about making films, that is what you will do, if you get out of the chair and actually make a bunch of crappy ones, then at some point, they will get less and less crappy and that discipline of doing it will serve you well, as they say in sales that old asian proverb
"salesman who covers seat instead of territory always stay on bottom?

"I can flat out tell you IT IS AN EQUIPMENT PROBLEM" well it is easy to determine, go to a music store or rental house and substitute equipment and test and see. What concerns me with the OP is why buy equipment that doesn't work? I am not emotionally invested in this, I am not putting him down, but when I buy equipment I test it out and if I order it, I return it within the return time. Everyone has a first day on their job, so their is no person born with audio knowledge. Guy it seems a bit naive on your part to say emphatically that it is the equipment. You don't know and neither do I. Kind of like devout religious person who knows, really knows the existence of God. So why buy equipment that doesn't work? likely because they do not have a good workflow with the equipment and are unfamiliar with audio techniques. However if the problems persist with new equipment then you have your answer and if you swap out the recorder or the microphone you have it too. I always test equipment prior to purchase or within the return period. Audio 101

I am an audio guy, I strongly suspect that the problem is not in equipment, but instead in your technique with that equipment. Shure has a free pdf on stereo recording. However hardware solutions are no solution if the problem is technique. I am not saying it is or it isn't. Just something to consider.

Stupid and naive are not the same thing, Naive is not knowing the difference. Your own words reveal the answer.

obviously I don't know you or this situation, but seems a bit naive all the way around. Naive from the company stand point and possibly naive from seeking our input where if you are a true professional having this figured out already. Not being snarky here, kind of like the surgeon saying "where is that tool with the sharp edge" Since you have asked my advice, here it is https://www.youtube.com/watch?v=1-mOKMq19zU