My (30M) gf (29F) says Snapchat is lying

My (30m) gf (29f) and I have been together about a year. She has a few male friends which she snaps on occasion - I don’t love it but they grew up together so it’s not a big deal. Personally, I’d love for us to delete it altogether.

Today, she went to send one a snap and in her recents list was a guy I’ve never heard of. She said it was a friend of her ex husband. I asked why he is in her recents and she said she has no idea, she hasn’t talked to him. Her immediate response was “you don’t trust me” and “I’m not lying, it’s just there.” Snapchat says “invite to Snapchat” as if he doesn’t have an account, but I don’t understand why he would be her last person under recents.

If she’s lying about snapping a guy, then we have a bigger problem. But has anyone heard of this or seen it? I don’t get how an app would magically “lie” about that.