Remove that mold!
If you added the moldy grape pack to the must without knowing, I'd probably add meta to try to kill any spoilage organisms that may have followed the moldy grape pack into the must and let it sit for a day or two before adding the yeast.
If you didn't add it to the must, tif you didn't add it to the must, don't add the meta before pitching the yeast, But take lots of pics to document it in case the company that you purchased it from wants proof, you may even want to put that container in a Ziploc baggy in case they want it returned.
As Knockabout stated, continue making the wine without the grape pack.
Absolutely contact the shop that sold you the kit and RJSpagnols, let them know that you feel uncomfortable making this kit seeing that a major part was either packaged poorly or infected, you shouldn't have a problem getting a replacement kit, what you do with this current kit after that is up to you, I'd still make it unless it smells sour, like rotten eggs or like vinegar.