Face search services often rank results with a similarity score. It describes how similar two images appear to a model; it does not verify identity. Providers use different models and indexes, so scores are not directly comparable between services.
Lighting, angle, resolution, age and image edits can change a result. Even a high score may refer to someone else. A low score does not prove that a person has no online presence. The useful next step is to inspect the source page, its date and the image context.
AHMLock displays source links alongside results. Compare several independent clues before drawing a conclusion. Never use an automatic match alone for a decision with serious consequences for someone.