Recruiter asked about my background, asked what I was looking for and explained what they were looking for. He said he thought I'd be excellent for the position. Told me he'd get back to me concerning the decision to move forward... but just ghosted me even after I reached out? Quite unprofessional to assure that I'd get a response and then never reach out again.

Just ensure you prepared for interview and the answered it confidently. Half of the interview question is about your work experience and how you deal with challenges. The other half on general billing questions and credit memos.