Macmillan Learning Economics Content Developer and Support Representative interview questions

I was contacted by the Recruiting Manager to apply for this position. I had submitted two applications to this company prior to this one. The first time, I applied for a freelance content writing position (Economics author), via their online posting and option to apply with LinkedIn. I never heard back regarding that position. A month or so later, a contact in the company told me they were still looking to hire positions within the Economics department; I found three postings online that I was qualified for and applied via LinkedIn for all three (an author for a principles-level economics course, an author for an intermediate microeconomics, and a content developer/review position). I received an email shortly thereafter (maybe 1-2 weeks? I don't remember exactly), regarding my interest in authoring for the intermediate microeconomics position. I was asked to submit a writing sample within 3 days (they give you a general topic and multiple parts to complete regarding that topic). I worked on the sample for three days and sent it in. I never heard back from the company regarding my submission. About five months later, apparently they had a content developer and support representative position open up. The Recruiting Manager called me after finding my previous writing sample on file somewhere, and we had a phone conversation/mini-interview for about 15-20 minutes. She sent me a writing sample to complete for the new position, to complete within 4 days. (This sample was much easier, since the material was more focused for a principles level course than intermediate.) I completed the writing sample and sent it in. I got an email saying that the document was received. One week later, I called to follow up on the application since I had not heard anything. When speaking with the Recruiting Manager again, this time I felt like a burden and an annoyance, which was inconsistent with our previous interaction. She told me she would look into it and get back to me by end of day. By the end of the day, I got an email saying that they were pursuing applications with other candidates. By talking with my contact in the company and some other people there I have met, it sounds like the original position(s) I applied for were probably closed and no one was hired. Furthermore, I've been told that Sapling rejects about 80% of the people that apply as content authors and that the writing sample part of the application is extremely challenging to get through. Finally, I had met all of the qualifications for this position; however, I have an M.A. in economics, not Ph.D., which is a potential reason for others to appear/be more qualified than me. I have also actually worked with the Economics elearning module that Sapling has produced; I am quite familiar with their work and their style of modules.