If it's not part of the agreed upon scope and they didn't ask for permission, I see no obligation to pay them. They can put the logo in context, sure, but if th

If it's not part of the agreed upon scope and they didn't ask for permission, I see no obligation to pay them. They can put the logo in context, sure, but if they end up spending more time on the sketches for that context than the logo itself, that isn't what you ordered.