The obvious solution is for the airport to hire a commercial operator to fly another drone into the one that's being flown.
I strongly suspect it's operating on a pre-programmed GPS flight path. I doubt the 'operators' are anywhere in the vicinity, although they could be anywhere in a large search radius.
If it has a camera on board, it'll be underneath, leaving a huge blind spot. All the other drone has to do is descend upon the target from above, interfere with one of the props & the errant quad will be downed in seconds. No need for bullets or complicated net delivery systems. It really is that simple. I'm amazed no one's thought of this already. Even if the controlled drone is damaged beyond repair in the process, it's only a few hundred quid, instead of tens of thousands spent on diversions & passenger accommodation.
The propellors on most of these are pretty fragile. If the drone being taken down demonstrates any evasive manoeuvres that must mean the operator is within sight of it, meaning they could be apprehended. And if the downed unit is recovered, it'll have GPS log data onboard - including where it took off from.
I'm glad I sold mine several years ago!