Selling out means to gain at the expense of others…. Are you doing that?
Marketing is like money; it’s neither inherently good or evil – it’s what one does with it that makes it so. It depends on what you are promoting… Do you believe you would be causing harm by taking this job?

One theory is that you would selling yourself out by not accepting this job, because you would be staying in a low place, struggling to make a living. This job could help you out of survival mode and help you upgrade your skills and find a sense of purpose. You don’t have to stay at the job forever, but once you get some experience, you could transfer your skills learned there to something else if it’s not the right fit for you. It can be a stepping stone to getting yourself to a higher place and it could be a great opportunity if you put your heart into it. I wish you the best on your path…