From what I have been told (and have seen in the sim) only a/c "flights" in your "package" can be seen in your Data Link.
Yes that Is how I also understand it but what made me confused is
1) In the mission briefings you are for example instructed to "..rendezvous with package.." at a specific point but the strike flight and escort flights are parts of different packages (Falcon1 being the SEAD flight and Serpent1 being the escort flight). When I ask AWACS about the vector to the package then I get the heading to where my wingman (Falcon12) is and not the escort (Serpent).
2) Not once during the campaign have flights being generated so that they are part of the same package.