The issue is scriptural truth. Earning your salvation is not possible, and anyone who believes that their salvation is due to their works, or the words or actions of another human, is deceived, and definately headed to hell.
The fear of the Lord is the beginning of wisdom
The issue is not whether your grandma was a member of an organized religion, but whether her "God fearing" meant that she has accepted Jesus. If she was truly God fearing then she probably had. And she probably wasn't working like she did, to earn her way into heaven, she was probably working because she loved God and she loved people.
If she hadn't accepted Jesus, all those works won't save her and they are in vain. But I suspect that she had accepted Jesus.
Jesus said it was the ones that loved Him that would obey Him. Paul said that the way we come to know what love is, is that God first loved us. So do you see the order.
God loved us first while we were yet sinners.
He provided His son to redeem us while we were yet sinners.
Because God loved us, we learn what love is.
Because God loved us, we develop the capacity to love back and to love others.
That love results in obedience to God and produces good works.
Jesus said that on judgement days there would be preachers who pointed to their works and Jesus would say "I never knew you". And Jesus would list the works of the righteous and they would say, "When did we do that Lord?"
It's the relationship that's key. Without that, all the works in the world are in vain.
You're in my prayers. God's word is all there is, and it is fully inspired. Read it, and believe it.