Yes, sounds like someone took them apart and put a xenon projector in them. If done correctly it can look Oem. I can’t say for certain though unless you have the bulb that came out of it. But since you said the bulb wouldn’t fit the new headlights I’m thinking they’re retrofitted. Any chance you could get pics of the current headlight where the bulb goes? Or you could google d2s bulb and confirm if that looks like what you took out?
Kbeanz 4th Gen OEM+ Projector Retrofit Build
Here is the first link I found of a retrofit, but there are many out there. What you could do is open up both headlights and the easiest would be to swap the new lense onto the old housing. Or open them both up and swap the guts from the old one and put it into the new one if you wanted.