There are roughly six skaters on Team Tut in that 9-13 year old age range: Dasha Sadkova, Alisa Dvoeglazova, Lyubov Rubtsova, Daria Sarymsakova, Margarita Bazylyuk, and Elena Kostyleva.
Of those six, all but Lena and Lyuba showed up in recent photos. Lena at least showed up in
a photo at the beginning of camp. So, yes, I agree that it's most likely that Lena just left early to join her parents on vacation.
Lyuba, however, hasn't been seen on ice at all for three months, it sounds, and was posting vacation photos smack in the middle of camp. She's about 12.5 years old. Like Alisa, she turns junior next season, i.e. 22/23, and she's eligible to compete at RusJrNats this season.
So, yeah, she's not at the age where you'd expect her to be absent from camp unless there's good reason for it, such as an injury or a departure from Team Tut. Inquiring about this is hardly suggesting a conspiracy.