--Previous Message-- : : I think it is the Duke of York in Windsor : Uniform. :
No,this gentleman is not The Duke of York. HRH sits much closer to the 'important' part of the table and none of the ladies sitting left and right to the mentioned gentleman resembles the companion The Duke has when entering St George's hall.
One can see The Duke on the bottom-left corner (with Garter Sash). The picture with his companion is further down.
In the background, one sees The Duke of York with an unknown lady who apparently is his dinner partner (she can be spotted sitting on The Duke's right hand side in the pic above)