I see you use Romans 8:1, but you didn't complete the entire verse. It goes on to say "There is therefore now no condemnation to them which are in Christ Jesus, who walk not after the flesh, but after the Spirit."
There is therefore no condemnation to them which are in Christ Jesus who walk what, NOT AFTER THE FLESH, but after the Spirit.
If we are caught in habitual masturbation and we never repent, that is turn to from it and forsake it, and we die, then we are walking after the flesh and not after the Spirit. How can you say that he is not in danger of eternal damnation? The bible makes it clear
1 Corinthians 6:9-10 "Know ye not that the unrighteous shall not inherit the kingdom of God? Be not deceived: neither fornicators, nor idolaters, nor adulterers, nor effeminate, nor abusers of themselves with mankind, Nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners, shall inherit the kingdom of God."
Masturbation is fornication. If you are unrighteous in your masturbation, your fornication, you will not inherit the kingdom of God. That's not what I'm saying, that's what the word of God tells us.