I ran into a similar situation when checking an older car that still had a 13 digit VIN. At first it felt like most modern services would not accept it, but after some searching I realized that useful information can still be found if you try the right tools, including resources like
https://carfast.express/en/window_sticker/ram that focus on factory data. Looking at examples like a window sticker lookup ram helped me understand how original options and build details can still be traced even when the VIN format is older. In the end it is worth trying different sources instead of assuming that an older VIN cannot tell you anything helpful.