I'll try here. I had semi-sweet chocolate bits melting to coat little truffle - like cookies for an 18 year old's bake sale. Realizing there wasn't enough chocolate , all I had and added was a bag of Ghirardelli 60% cacao bitter-sweet morsels. Probably first mistake. Although the mixture melted it just wasn't loose enough to coat the truffle-likes. I said out loud, second mistake, I wonder if I added milk, would that thin it out? Left the room for a moment and she had added milk, cold. It siezed up solid ! So, question is - can It be salvaged? Is it worth salvaging if it can be or just give it the big See Ya. I know NOTHING about baking but learning.
If you heat it and add more milk, cream, or even water, the mixture should loosen up and be like ganache. If you add butter or oil then you can use it for coating items, provided you don't add too much. In the future, remember if you want your coating chocolate more liquid, always add fat to it, not liquid (unless you want ganache).