Your Call of the Wild (COTW) supplement appears to be dangerously high in iodine.
According to the label instructions 1 tsp of COTW is to be used per 3 oz of meat.
Using data from this document on your web site:

COTW contains 92.50 mg/kg iodine or 0.0925 mg/g
1 tsp COTW = 2.84 g

So we are to use 2.84 g COTW/85 g meat
Assuming a fairly typical 80% moisture for meat:
2.84 g COTW/16.8 g DM
2.84 COTW has 0.2627 mg (2.84 * 0.0925) of iodine.
So our food will have iodine content of 0.2627 mg/16.8 g DM or 15 mg/kg DM.
That is 43x the AAFCO recommended .35 mg/kg DM.
Could it be the information on your web site is incorrect?

Thank you for your recent e-mail.

The current formula of Call of the Wild™ contains 45.5 mg/kg of iodine. Batches can vary depending upon the type of kelp used.

There are 0.326 kg (326 g) of product per bottle of the Call of the Wild™, which would be 14.8 mg of iodine per bottle.

There are approximately 91 teaspoons per bottle, which would be 0.163 mg of iodine per teaspoon. That is how much iodine a pet would be getting from Call of the Wild™ if ingesting 1 teaspoon with a meal.

With regard to evaluation pet foods based upon percentages, see: Does Your Pet Need A % Of Something?

With regard to the iodine inadequacy of modern foods, see:

As for feeding amounts, no calculation is needed. It is recommended to add 1 teaspoon of the Call of the Wild™ per 3 oz. of meat/food.