Although I am a Christian, I feel it is incumbent upon us to respect the beliefs of others IF THEY DO NO HARM. Your friend seems to have led a largely decent life and paid due respect to the Creator and His laws. My view is to accept what others believe, as HOW people worship is more important than WHO they worship. My condolences on your loss.
The Jewish unbeliever thinks that although he isn’t perfect, God will find something in his life is righteous and will save him.
The Muslim unbeliever thinks that while there is much to be done to achieve perfection, as long as one good thing is done and unrighteousness is opposed, God will count it as righteousness.
Both perspectives are fundamentally flawed in regards to justice.
Whatever the unrighteousness presented to God, His Perfect Righteousness demands Perfect Justice. Likewise whatever unjustness is presented to God, His Perfect Righteousness demands Perfect Justice.
The only way to provide perfect justice to perfect righteousness is to provide it in a right way. If provided without righteousness, it will still fail to be labeled righteous by Perfect Justice.
Jesus Christ remained faithful to God the Father, by submitting to His Plan, even to the Cross, even unto death, submitting himself as the Perfect Sacrifice. Without that perfect sacrifice, nothing offered by anything or anybody which has ever been associated with anything not in or by His Plan, i.e. sin (missing the mark), will ever be qualified as righteous before a Perfect Judge. Without faith through what He provides, we have no redeemer.
Muslims and Jews might produce many humanly good works within this domain, but the Divine domain, where only good works by Divine standards are not burned up are ever admitted for eternal presence with the Divine and other righteousness.
You might want to call your belief something else. It is anything but Christian.