Ground moves on Express aircraft every single day to several remote locations, including Alaska. This might make sense logistically, but it is mixing one mode with the other (Ground via Express). I am also aware of Ground tractor-trailers delivering Express freight to an Express ramp. Again, a mixture of modes. Express CSA's handling and processing Ground freight. That's 3 times. Sounds pretty integrated to me.
The degree of integration might not be exactly the same as UPS, but Express and Ground are definitely NOT separate and independent companies. FedEx would like you to believe that. I know otherwise.
Here's your proof. Ask your manager to access the flight information for the aircraft that fly to ANC. If he/she can pull-up an FDR, you'll immediately see Ground freight moving in LD3's on the manifest. Do it, then get back to me with what you discover, OK?
My bet is that the manager will refuse to do it. If you're near a ramp, ask a ramp agent to print-out the ANC flight(s). If you have access, you might even be able to do it yourself.
Finally, ask yourself why Express would want Ground to have an Express-capable computer and tracking system. Again, I await your brilliant answer. Ask bbsam if you need some help.
It makes sense to fly the Ground freight, otherwise we would have to drive it through Canada, be subject to their customs laws, and it would likely be more expensive than putting it on a plane that is already going to ANC. Also, Ground pays Express for that space, much like the USPS pays for space to fly their mail. Sure, it's just taking money out of the left pocket and putting it in the right one, but we (Express) don't fly it for free.