My device was stolen. And Find My IPhone was somehow disabled

That's most unfortunate. If Find My was not enabled, there is no way to track a lost or stolen iPhone.

See this link for more details --> If your iPhone, iPad, or iPod touch is lost or stolen - Apple Support

Having the Serial and IMEI won't help you. You do need to notify your carrier and ask them to blacklist the phone if they offer that service.

At this point, you will not be able to track or locate your iPhone using Find My. Your remaining choice now is to find the iPhone by looking for it physically (if feasible).

Axel F.