Sunflower top half cross model is not mirrored on the back

The current behaviour is without a doubt intended as per MC-96463 (refer to ticket's history) and the Works As Intended resolutions of MC-199241, MC-199248, MC-202595, MC-202598 and MC-206570. Please focus on fixing all other currently open plane-mirroring tickets.

Note how the targeted leaf section does not appear in the same place on the back of that plane.

Fixed model attached.