In that case, why does the config want the product name? That string isn't used for anything as far as I can tell. The name of the ingot is formed by the ore name plus "ingot".
I used Minetweaker to register the ingots and it was incredibly slow, roughly 25s per ingot on world load. The dusts were instantaneous however. I think it's just easier for me to add Tinker's Construct smeltery recipes for metal flakes themselves to sync the behavior up with native flakes.