Right now all we know is that one specialist is using a "drone" / "auto-turret" .
It shouldn't be a "call-in" at all, more a gadget, then I would like your Idea.
As a gadget, a drone can't be a big UAV at all, but a smaller one, so it would be like the older "Star Wars Battlefront / Star Wars Battlefront 2 / Frontlines Fuel of War" Recon drones alike. You can use them in a specific radius, they do some damage but they are not an overpowered gadget that you can call in for your points. Because your squad, your team is playing the points, so they should all benefit from it and not only the "Squad-leader" which implifies your Idea for me at the moment.
For a call in, some sort of big UAV would be nice, which you can control similiar to the good old Gunship like the one from BF4.