I doubt it if that is the case why Pakistan bought ZDK03 from China My understanding is the ZDK is the AWAC for JF 17 and Fireye is for F 16
No country will allow their data link to be modified specially NOT the US
U.S doesn't allow is one thing, but countries still try and have met with success. Australia is one example, with their F/A-18s and then there is that tiny Israel that seems to get its hands on every technology available in the western world, and managed to access certain areas made inaccessible by manufacturers.
Pakistan is no exception to this case and has ventured into systems development, independently. It's not publicized as something grand, because it is not publicized at all. Doubting that Pakistan is able to do something this risky or difficult, is one ace they hold up their sleeve!