Hey! I had the same issue during my interview. It was explained to me that they didn’t have the correct “copy” of the K1 petition and they had to request it from the service center. It did take us a while to get approved after our interview, but that may be because Baltimore is notorious for taking a few months, rather than because of this issue.
Your wife can definitely travel on her EAD/AP card after your interview. I did and I was completely fine! It doesn’t lose its validity.
Hope this helps, and please hang in there! I got my approval notice today and had the best moment with my wife - we are finally done (for now!).