Is it possible that she just misunderstood what you wanted, you said you showed her a picture but if you continued to say 'short, short, short' she may have for whatever reason read between the lines and determined that you wanted topknot and ears short too. Another question for you is are you sure your groomer offers dematting services? I for one do not, if he's matt tuff he's shaved. Sometimes I'll dematt heads/ears/tails once or twice but if they keep comming back matted they come off. Now here by dematting I mean I dematt slightly matted coat, not matted to the skin coat, that is never an option with me. From the way you worded your post I assume his topknot and ears fell into the slightly to moderatly matted range?
Another point to make is that she may have attempted to save those areas but wirggly won't tolerate it. It might have been a judgement call on the groomer's part, somthing along the lines of 'hey this is obviously hurting I'm going to stop and just clip it".
All that said, and assuming she understood 100% what you wanted you are right to have expected a phone call. If she didn't understand... well then thats a whole differnt situation.
As for price, I feel you should have paid full price personaly. I do understand though what you are thinking in figuring this haircut should have been cheaper because as a shave down you figure it would have taken less time. What you are not taking into account is that the haircut you described as being nice, a #5 all over with a #30 FFT IS A SHAVE DOWN. So it would take the same amount of time regaurdless of length of coat, it's still a blade on the body, does that make sense? The topknot doesn't take a decent groomer all that long to trim so really the groomer didn't save much time. Also take into account time your groomer *might* (you'll have to ask her if this was the case to be sure) have spent trying to save the topknot. The only time I charge a client more or less in relation to length of coat is if we are scissoring all over and are going from that scissored all over clip to a blade or gaurd comb. In those cases it certainly DOES take less time and effort.
Also like a lot of other groomers I know I personaly always charge extra if your dog is matted, I like the speeding ticket example, good one
Every groomer is differnt so it may just have been a case of miscommunication. We all have our off days as well so maybe she just had a brain fart. Had it been me and I found myself with a dog I didn't realize I couldn't save the topknot on I would most definitly have called, so I agree with you in being upset about that, I would be upset were I in your position.