The passport is supposed to be shot and profiled under all the different scenarios you're shooting, not a one time deal that you plug into the camera at all.
I don't know if theres a misunderstanding but thats what i'm reading from your posts, we shoot the color passport at the beginning of each shoot after having set-up all the lighting, or in every different ambiance. We then import and can create a custom color profile for each camera for each set, so that the colors are technically correct and match each other across the different sets. After which we'll generally fine tune the colors to our preferences.
The profiles you can import into your camera aren't about color accuracy, moreso just adjusting to taste, i have a couple Velvia custom profiles, but i have to admit i never use them, the video folks use color profiles much more often, but they use low contrast ones to capture as much as possible before color correcting themselves in post.
Outside of LR, through DPP, i find the faithful profile to be most accurate and pleasing with low contrasts, just a question of having the right WB.