HFCheung

I think this is a very good candidate, but not conclusive to me.  
The ring around the ear, and the slightly paler area in the centre of the ring are very good features.  However, there are also doubts to me.  For example, the ring around the year can depend on angle of view, and many Citrine Wagtails would have a thicker wingbar.

I hope there are more photographs.

HF Cheung