If you do not believe in God nor the Christs salvation for you then you are not known by the Christ as you put it. If you know of the Christ and refuse to accept then NO you aren't going into God's heaven. It isn't about being good nor gaining points nor a tally of good and bad behavior! (He is not santa claus you know), He is God. You cannot earn nor buy a place in His Kingdom, you must give your faith to Him and live as He wants you to. It is by His Holy Grace that He accepts your faith in His salvation that we are permitted to be seen as pure and clean. That is what is required to live with God in His Kingdom forever.
There will be many pagans that will be known by our Christ because they did the best they could with what they had: and where some men and women today did have one heck of a lot more than the ignorant pagan from thousands of years ago; they will be going to hell too!!! To whom much is given much is required. Insurance religion and lip service just doesn't cut it.
Do you understand? It is by the Christ you get into God's kingdom, He will know your heart regardless of whether you have ever heard of Him or not.
He knows His church, He knows His brother and sisters, He knows His flock, and we know His voice, He knows who the counterfeit Christians are and He knows who the evil are.
Unbelievers who reject the Christ will be rejected.
What else would they expect?