Did I get it right that you are no seeing photos synced down to Lr Desktop which you have imported on your mobile device?
If so, could you please send me a LR Desktop diagnostic log - best as a private message with a downloadable dropbox link.
You can trigger the log via LR Desktop preferences -> Lightroom Mobile and when you hold down the alt key you will notice a generate diagnostic log button. - Guido
Thank you very much for looking at this for me. The links you have requested have been sent.