Teach for America Development Associate interview questions

I applied in mid-April online and instead of a phone screen or first round interview was sent an assignment around four weeks later in May. I completed it in time and even had my Development Consultant friend look it over- I spent several hours on it though the instructions mentioned that one should not spend over 1.5 hours. I sent an email asking about future interviews and my status, and soon after- about a week later- got a generic email saying they pursued other candidates and thanking me. Fine. Then, I emailed this manager asking if I could get some quick feedback on my assignment, to inform my approach for future development assignments in interviewing- which I've found to be fairly common. She agreed and said my assignment was "really thoughtful" and that we could talk on the phone the following morning. The following afternoon I call her, and ask if she has a minute to discuss my assignment, she says yes. So I ask a couple of questions like, "What are you looking for in completion of the assignment?," "What did you think I could have done better in the assignment?" and "What did others do which was more competitive for this assignment?" She gave me nothing. Like actually, nothing. She just repeated that it was "very thoughtful," but gave no actual specific positive or constructive feedback. So, I am not sure why she agreed to speak with me about it in the first place, since she apparently had no opinion she could share, even with it in front of her. I did not schedule the call, so maybe she was caught off guard, but overall it was an uncomfortable interaction which suggested that the TFA process for selecting development candidates is either not thorough, not transparent, or both. I would hesitate to apply to a position in that department or with TFA again in the future because of this experience.