Hub caps aren’t serial numbered to the very vehicle they came from,
but PART numbered as to the brand and type they are made to fit.
That will get you close to the vehicle. What brand logo is on the front ? What names and numbers are on the back ?
Visit the dealer for the brand you see and they’ll cross the stamp number to the part number and know which vehicles it was made for.
The ‘‘green’’ fiberglass…is that the outer body color or just generic structural color ?
Is it actually fiberglass ? plastic, bakelite, carbon fiber, or other composite ? THAT can be a clue too.
If it’s the outer body color, those are sometimes unique.
Take it to an auto paint wholesaler for a color match and it might just be brand or even model unique.
Those paint shops are not well marked for the general consumer and some body shops mix their own paints.
Ask any body shop, dealer or indy, for guidance on the paint color.
Are you close to the bar they were coming from or perhaps closer to their destination ?
In the daytime check around the neighborhoods.
at night cuise the area bars and look for vehicles with related damage.
Post some pictures or all the numbers and words you can see, even partials.