This has been my understand as well. I have CKD and my doctors have always been chill about it as long as I stop taking it about a week before having blood work done.
EDIT: I don't do 25g though... sounds like a lot...
You're lucky your doctor is aware of it. I've had several who did not understand, and insisted creatine must be dangerous if it elevated creatinine levels, and/or didn't understand the effects.
If your egfr is above 80 it’s you won’t notice it. But CKD is a late in life problem so you are basically making your end of life worse by making your kidneys work harder now. You might as well take up smoking: claiming it doesn’t hurt now is a lot different to 20 years of constant use.