As I said, Yeme connected to the Dinosaur age. In the "Annihilation of the Dinosaurs" project, she already connected to a reptilian lady, mentioning that she was welcoming her. There's definitely a connection between that project and Lacerta.
At one point in the Lacerta session, Yeme wanted to look through her eyes to see what she is seeing, and saw a human in front of her – which would be Ole, the interviewer.
Maybe Lacerta made herself bigger for Yeme? But I don't think that's the case, as she is complaining that she has to make herself smaller than she really is.
Maybe Lacerta lied to Ole about the size of her people? That would be more believable.
Why do I think that Yeme talked to Lacerta? Because Lacerta/Soraya is not a simple student, as that explanation makes no sense at all. Quote from the PDF, page 50:
"Question: You said, you would not have had permission at that time for contacts with human beings. Do you now then have permission to talk with E.F. and me about all these things and even to make this scientifically public?"
Answer: Yes. That is difficult to explain and for you to understand. Let's just say, I find myself in the position now to arrange this permission without having to take into account any consequences. In this position I am quasi-"immune" against certain restrictions. Let's look it that way. Yes."
Without having to take into account any consequences? My guess is that Lacerta actually is the "queen" of her people. That's why she's so concerned about the balance of the forces.