Exactly what do you mean by "in the cloud"? Do you mean that the images are available when you use a web browser and log into your lightroom.adobe.com page? It sounds like this is the case. So what you have done is sync the images from LrDesktop, but what actually gets synced is a "smart preview", not the original. When you download them from your lightroom.adobe.com page, these will produce a smaller panorama.
Now, also included in your CC Subscription is 2Gb of disc space. This is completely separate from the Lightroom (and lightroom.adobe.com space) and it acts like Dropbox or OneDrive, if you know those. Anything you put in the CC folder (in Finder/Explorer) will be uploaded at full res. So in Lightroom, you could add a new folder (the little + in Folders) and navigate to the CC folder, then create a new folder in it. Drag your originals into this. At the office, you should then have the originals available via the CC app, and it will sync them down to the computer.
Does that help?
Assuming you created the panorama in Lightroom on your Mac, and then synced it to the Adobe servers, then you can't access the original from LRWeb on any system.....Lightroom on the desktop only uploads a Smart Preview (2560px long edge) to the server, not the original. Only LRmobile and LRWeb will upload an imported original file, which can then be downloaded using LRWeb on another system.
It would be possible to achieve what you want, although it's a bit clunky. For example, after creating the pano in LRD you could Ctrl+S to save the metadata into the file, then remove it (without deleting it from disk) from LRD. Locate it in Finder, and drag and drop it into LRWeb running in your browser on the same system. That will upload the original file to the Adobe server, which will then download back into LRD as well as being available in LRmobile and LRWeb on any other system (though viewing in LRWeb only uses a jpeg preview I believe, but you can download a copy of the original for viewing/use in another application).