As-Salam Alaykum,
Matters of judgement ultimately belong to God. However there is some wisdom that can be extracted from the Quran regarding this issue. I believe brother Joseph addressed this in some way or another. Let's ponder on the following passage:
[6:75]And thus did We show Abraham the realm of the heavens and the earth that he would be among the certain [in faith]
[6:76] So when the night covered him [with darkness], he saw a star. He said, "This is my lord." But when it set, he said, "I like not those that disappear."
[6:77] And when he saw the moon rising, he said, "This is my lord." But when it set, he said, "Unless my Lord guides me, I will surely be among the people gone astray.
[6:78] And when he saw the sun rising, he said, "This is my lord; this is greater." But when it set, he said, "O my people, indeed I am free from what you associate with Allah.
[6:79] Indeed, I have turned my face toward He who created the heavens and the earth, inclining toward truth, and I am not of those who associate others with Allah."
ٍImagine if God had taken the life of prophet Abraham while he believed he's lord was the Star or the moon or the sun. Would he be treated equally as those who blindly worship these entities because their forefathers did so ? Arguably not.
Prophet Abraham was in a journey of the pursuit of truth. For it to unfold it required effort and sacrifice. Truth is not handed on a plate. Prophet Abraham had a sound heart (37:84), it was a matter of time until he reaches the final stage of truth.
Similarly, there are those who follow narrations who also have a sound heart. They do not do so out of blind following. Instead its just the best argument they have been able to reach. And as soon as a better argument manifests itself to them, they will arguably accept it just as prophet Abraham did.
I would like to end with brothers Joseph's sentiment:
We should endeavour to reserve an inclination to judge anyone else in matters of their faith or their sincerity of pursuits. How could we? How could we ever begin to know their PATHS, the matters of their hearts or what is right for them AT THAT POINT in time of their lives? [1]
Regards
[1] [Varying degrees of truth]
https://www.facebook.com/joseph.a.islam/posts/206526606151141