Srt Canopy Anchor

Is it safe to use a Butterfly knot on a cambium saver like this? The Carabiner in the pic was flipped, didn’t see it at first. Reason i’m doing it this way is to advance my TIP on a tree where i can’t throw my line high from the ground. Or is there another easier method for advancing when in srt? I’m learning solo so i don’t know if im forgetting something