So sorry to hear about your friend. My condolences.
Remember, we live in time, but God is in eternity and can access past, present and future.
When your friend died, God knew you would pray for him in the future, and hopefully took that into account and had mercy on him.
A very pious old priest, who died 20 years ago, taught me to pray for people even if they'd been dead a long time.
Do offer the prayers for the dying for your friend. God is merciful.