Welcome aboard... bummer! I was in the same spot as you a few years back. You are correct, Dometic windows are not intended to be unlatched while driving. I had to replace the large one over the dinette because I left it cracked open when I forgot top shut it.
I am not a fan of this type of window... you can read my critique
HERE.I got mine form the factory, have you tried calling Palomino to get one?
Perhaps you might try
Five Star RV. They are located just north of Denver and have an RV salvage yard.
Post a picture when you get a chance. This site is kinda' wonky to add images. Use
THIS LINK to create a string to upload photos.
Sold the TC, previous owner of 2 NorthStar pop-ups & 2 Northstar Arrows...still have the truck:
2005 Dodge 3500 SRW, Qcab long bed, NV-6500, diesel, 4WD, Helwig, 9000XL,
Nitto 285/70/17 Terra Grapplers, Honda eu3000Is, custom overload spring perch spacers.