Are there clips in the rear screen windows?
On our 2009 the screens have a what I call a V type plastic piece or wedge that keeps pressure on the screen when installed. I don’t have a picture for you but perhaps someone else might.
As a suggestion, you might find a couple of Bobby Pins, cut them to size and spread them to increase tension. Then superglue them into place. If you look at the springs in the other screens you should have an idea of the size.
Hope this helps.