Please remember there’s a LOT you (and I) don’t know - STARTING with an individual’s relationship with God. Aren’t there Bible verses suggesting we be careful about judging what is in a person’s heart?
Absolutely, but you can tell a lot by their fruit:
“Watch out for false prophets. They come to you in sheep’s clothing, but inwardly they are ferocious wolves. By their fruit you will recognize them. Do people pick grapes from thornbushes, or figs from thistles? Likewise, every good tree bears good fruit, but a bad tree bears bad fruit. A good tree cannot bear bad fruit, and a bad tree cannot bear good fruit. Every tree that does not bear good fruit is cut down and thrown into the fire. Thus, by their fruit you will recognize them.”
Matthew 7:15 - 20