I mean… Beate is someone she barely interacted with, over the course of a few days that were several years ago, and she wouldn’t have had any reason to realize the level of Beate’s animosity towards her. And it’s not like there’s a shortage of people that Lottie knows have legitimate grievances against her, so Lottie not even recalling Beate’s existence isn’t that incomprehensible. It’s likely both Lottie and Claire completely forgot about Beate as soon as they got back to Tackleford, simply because there wasn’t much of a reason for either of them to retain any memory of her.