(2.2) isn't right. "I have never..." is used for something that you might potentially have done on arbitrary multiple past occasions (e.g. "I have never eaten crocodile" or "I have never visited Australia"). In this case you are mentioning one specific past occasion
Thanks GPY, As far as I know, "could" is only about imagine.eg. If I had money, I could help you. so how can I use 'could' for certain past. I think, "I could not join at the last class" is about imagine. How can I meke my sentence in past with 'could'. Please remove my confusion.