It's possible. This is ds1, who is now 16, so obviously it was a long time ago. I had the backache all night, and when I had light again, baby's head was up by my belly button. The doctor had felt the head down at the bottom (not engaged, but in vertex position) for several visits at that point. When the hospital staff found out he was breech, my GP accepted the "missed breech" diagnosis...but I never did. The nurse and intern (resident? can't remember) who examined me both noticed the head was out of position immediately. If ds1 had been transverse, I can't imagine that the GP would have missed it...
Oh, well - I'll never know for sure, but it is nice to know that it's possible. I've been told that "can't" happen with a first-time mom, because the uterus is too tight. (I let myself get bullied into my first RCS on a similar note, because the OB was so insistent that dd was "too big to turn" that late in the pregnancy - 39 weeks).