I need help removing insect marks from windshield

Tosh

I applied Glaco coating on the back and side windows with no issue and it looks good.
The windshield is in bad condition. I cleaned it with a glass cleaner, then with a clay bar and the glass cleaner again.

At first glance, the glass looks clean. But when I wipe it with a wet microfiber cloth, I notice numerous small, oily spots - residue from insects. These marks only appear briefly while the glass is drying (in the 2–3 seconds before the water evaporates). They’re not visible when the glass is fully dry or completely wet.

I don't want to seal them with the Glaco coating, but I can't find a way to remove them.
I event tried kitchen degreaser, it didn't help.

Please advise how to remove these spots.