I have to agree with l.cutler. I believe this is the result of glue or similar adhesive.
The apperance of this cent is clearly not a lamination problem of any known kind. Copper plated zinc cents do not have lamination problems. Any separation would be a plating issue. Clearly not a plating issue that I have ever seen.
Have you tried acetone yet? Acetone will cause most adhesives and glues to separate from most metals, including copper and zinc. If there is no adhesive, acetone will not attack copper or zinc.
Time for more coffee.