How did Mobius come to this conclusion?

Question

In the Marvel series Loki season 1 episode 2, the original variant from the sacred timeline gives a theory that

the dangerous variant is hiding in apocalypses

To test this theory Mobius and Loki go to Pompeii, and after returning from there Mobius realizes that the theory is correct.

I would like to know that what particular event at Pompeii made Mobius accept the fact that the theory of Loki is correct.

Answer 1

Mobius explains this in the episode itself. Loki was not supposed to be there and so anything he did should create variance energy. However, Mobius checks his device and sees none is created. That means that someone could hide in a similar event and not create any variance energy and so not get detected.

Mobius: I don't believe it. Zero variance energy. No branching in the timeline.