Never mind the “higher power” . You don’t need that nonsense to stay sober.
You, of course, don’t know what anyone in particular needs to stay sober. The concept of a “higher power” may not have played any role in your sobriety, but it has helped many turn their lives around.
As to the original OP, the steps of AA ask that the person wishing to remain sober acknowledge the role of a higher power “as they understand hiim” in achieving and maintaining their sobriety. It is not a Christian God, it is not a Jewish God, it doesn’t have to be God at all - whatever “higher power” you can recognize to take some of the burden off your shoulders as you start to get sober. I urge your friend to go to an AA meeting. Go back again. If that one doesn’t resonate, go to a completely different one. Sooner or later they will find on that fits.
AA and Al Anon saved my life and I heartily recommend the program to anyone who has had enough.