the mobile phone network has more than a grain of truth in it, but it wasn't used in Kosovo, it was a theory put forward by a british scientist to do what you said it would.
I think that in order to defeat stealth you have to look at what stealth (in the radar sense) is trying to defeat, namely radars that transmit energy and then receive some of that energy back again.
The principal effect of the F117's design is to scatter that energy away from the the receiving antenna which is usually on the same dish as the transmitter.
Now, if you network 2 dishes that are far apart, one on transmit and one on receive, and located them in a poisition along which you suspected a F117 would fly, you could transmit your energy and the F117 could conceivably scatter the energy towards the receiving dish, thus revealing it to the integrated system.
So called bi-static radars are not rocket science. Now all that may be speculation, but a few years ago, when Iraq was about to install fibre communications to integrate their air defence, we bombed the cr@p out of them.
An overreaction, as many thought at the time, or a pre-emptive response to a serious threat?