Probing under the outside edge of the window with a plastic scraper I could touch the inner window frame. I suspected the factory did not install any sealing foam or tape. I went ahead and pulled rear side window of the main slide. The foam seal was there, just useless. Another victim of poor construction.
Mold staring to form on window frame. Insulation below discolored from water:
Note foam tape around window frame:
This pic shows residue where the foam tape was positioned, no where near the edge:
Window ready to go back in with two layers of bulty tape: