You know what, I've actually tested it myself and the second map has loaded without any issues.
I think you misunderstood me, I didn't mean the Game Cache - I've meant renaming your map in the Campaign Editor. In order to do so, you have to export the map out of the Campaign Editor, rename the map while just like any other file on your hard drive, re-import the map into the Campaign Editor.
That's exactly what I did and the second map loaded just fine - though, I've used a "Chat Message" event to launch the victory trigger instantly, but if I understand your issue correctly, this should not have impacted the end result.
A picture for reference: