Sauce – still use the Worcestershire sauce

Rule #1 is always: When in doubt, throw it out. Nobody here can guarantee that it is safe. If you didn't pasteurize (or sterilize depending on acidity) then there is always a chance of dangerous contamination.

That being said, Worcestershire and and molasses are both shelf-stable while bourbon (alcohol), lemon juice (acid), and vinegar (acid) are all types of preservatives. So if that is the complete list of ingredients (no garlic or other perishable food) then the chances of this mixture developing any harmful bacteria, especially if it's been sealed and refrigerated all this time, are slim to nil.

I'd still throw it out. Your health is worth more than the $2 and 10 minutes it costs to make a new batch. Even if it won't harm you, it can't be very good in terms of quality anymore.

Enamel is a ceramic coating applied to the metal - it will typically be colorful and glossy-smooth to the touch. Raw cast iron will be black and matte in appearance, the unseasoned surfaces rough to the touch, the seasoned cooking surface will be smooth and a tiny bit greasy. Complicating things is the "black satin" enamel some manufacturers (including Le Creuset) apply to some of their pans to mimic a well-seasoned raw cast iron pan.

From the photo, you have a raw cast iron grill pan - we can tell, as it has been misused and the seasoning mostly removed. The coloration, going from black to grey, almost white, indicates the early stages of oxidation and rough scrubbing, and parts of the raised grill-ridges have likewise been polished from rough use.

While enamel can stain and discolor from use (Le Creuset calls this a "patina"), it's failure state does not include a metallic shine in places, and does include cracking or flaking. The glossy black bits stuck to the ridges are seasoning, and ideally should cover most of the cooking surface - if it were uniform across the surface of the pan, it could be enamel. As is, it's a great raw cast-iron pan begging to be restored with a good cleaning and re-season.