I'd definitely talk to the trainer after class and discuss your concerns. Apart from being incredibly rude, the other person's "methods" are different to your trainer's and might confuse the heck out of you and Malone.

We had a special guest from overseas at one of our puppy classes and I disliked her on sight (only about the second person in my life that I've felt like that towards!). No interpersonal skills and told me off for supervising Buffy when a group of kids wanted to pet her ("... if you are around, she'll never WANT to play with the kids.") And when B&S wouldn't sit, our trainer suggested holding their chests and apply some gentle presssure with the other hand on the hindquarters. Shane did that and the visitor said, "Well, that's the easiest way to give your dog a bad back, isn't it now?" He nearly chewed her head off for that one!

Sorry, I wanted to help you but I vented instead!