I do not know what color urine warthog may be having, however if you ever urinate this dark amber, brownish color they are talking about, you will know it is not the bright yellow or even darker yellow of B vitamins... you will also know it is not the color of urine after trying to re-hydrate your body after a dehydrating day.
You will also know, without doubt, that what ever is in that urine does not belong inside... almost reminds me of the color of dark leaded gasoline in a bucket.
I have noticed when I backed off of the iodine, getting the dark urine for a day or two after and then tapering off. Do note however that I continue to take the salt water, and magnesium. I get the bulk of my C through fruits and vegetables though I will dose C once or twice a week.