Cesium on a flaky network.

I have a web application that needs to support a flaky network. I am seeing a problem when a web worker is trying to access a file which has been previously cached. I have tried everything that I can think of html manifest, changing cache control on web server, explicitly defining the script in my index.html file, but nothing seems to work. I have been reading about Service Workers and the idea of an AppCache sounds like it is a potential future possibility. Is there anything in Cesium that I am overlooking that would make this work today? Or if anybody has any ideas how to tackle this problem I would greatly appreciate it.

Thanks in advance

J. Stoy

I have a screen shot showing that the createWallOutlineGeometry has been downloaded in the past, but it does not look like it is being read from cache by the web worker.

Link to browser network tools attachment: