I think as ( in this case ) there were 5 of them and one driver the time to reach the consensus would have been about a week prior!
5:1 or at best (worst?) 2:1 is still going to hold your head under water.
We are not talking about a bunch of tooth fairies from the bottom of the garden here.
This is the second such occurrence in Grasse and there was one in Sydney a while ago. In all cases the pilot and aircraft were left unscathed. They are not interested in wasting time dealing with things like the pilot or aircraft and are more interested in keeping the upper hand by constantly changing the game.
They know about your Apache, but they also know it takes time for it to mobilise and find them. Simple - remove that opportunity.
On the day there were two Alpha Jets on the tarmac at Nice (with all the plugs in) and these guys if they were on track flew within 5 miles of Le Luc / Le Cannet where more than one EC665 Tigre, amongst others, is known to reside.
With respect to your Eurofighter scenario - even if you did know which way they went could the radar pick out a helicopter at 100' doing 80 mph over the M1? Considering the traffic is moving of course!