Strange film on windshield

[Supergus1]

I recently bought a low mileage 2018 Silverado truck from a dealership, and a couple of weeks later I had a detailing shop coat the paint with Optimum Paint Guard, which came out great.
When I picked the truck up I noticed some kind of coating on the windshield. It looks like an oily film; I showed it to the shop owner and he tried cleaning the inside and outside to no avail. I asked him if they sprayed on the coating prior to wiping it, thinking maybe it was OPG overspray (I didn't know any better, never worked with OPG) and he said no, that they wipe it on working very small sections. He then pointed out to me a small decal on the windshield that said "AutoNation Appearance Package". Now, I'm 100% sure that the film wasn't visible when I bought the truck, but is it possible that: #1-that whatever coating the dealership may have put on the windshield, that the 105 degree days here in Texas have degraded or altered the coating? Or #2- that the various chemicals inside the detail shop reacted with the coating?
I've cleaned the inside and outside with Perfect Glass cleaner with no success so I'm wondering would steps I should take to remove this weird film? Also any other thoughts would be appreciated. TIA

[The Guz]

Polish the glass and see if that helps.

[Supergus1]

I was hoping to start with something less aggressive but is there a glass polish that's a relatively fine compound?

[Eldorado2k]

I was hoping to start with something less aggressive but is there a glass polish that's a relatively fine compound?

Yes, Mckee’s High Performance Glass Restorer. I’ve had this stuff work near miracles on automotive glass.



You could also try 0000 Steel Wool.