@1230vani,
The diesel is harder on the passenger side as there is the AdBlue tank sitting behind it. I did got first hand experience when installing for one of the forum member X5 35d. He changed the grill into an open grill, so I uses the opened section to stick my finger in and push the locking ring into place.
I tried opening up the bottom cover, but it didn't help me much in securing the locking ring. One thing that I didn't give it a try and I just recently thought of it. Maybe by taking off all of the screw holding the bottom of the bumper to the chassis will allow you to push the bumper out a little bit and reach in to place the locking ring.
But, looks like your glue and 2 locking rings are holding up.
