I would certainly find another trainer too.
Puppies are like kids, bouncy, mad and full of life. I have found over the last two years of working with my dog in classes and closely with my dog trainer that people expect far too much of their puppy or come out with some very odd notions that they themselves have thought of or have been told by trainers!
Regarding dog training, make sure you go to a trainer who is IMDT certified most of all. This means they are a member of the Institute of Modern Dog Trainers who promote rewards based training which is the only way forward and the most effective. Make sure they have other qualifications and are members of guilds dog trainers, pet handlers and so on. If they've got professional qualifications as long as your arm, brilliant.
If they've only got years of experience and come out with phrases like "I've been doing it for X years, I know what I'm doing" steer clear.
My dog trainer is IMDT certified and has a whole slew of other qualifications and she is constantly on courses and further improving herself. She is a delight to work with and all the dogs absolutely adore her.
Regarding food, there is nothing wrong with high protein and most dogs get on with it fine. There are some that don't though and for them I recommend a 60/40 formula such as Canagan where as brands like Orijen are 80/20.
Canagan is suitable for all life stages and is a very good alternative if your dog doesn't get on with a brand of food like Orijen. In my opinion a dog food should be high meat content, vegetables, fruits, botanical extracts and nothing else.
If a food has got rice, oats and in particular maize, I'm not interested!