100% bugger all to do with the key or the induction loop on the ignition barrel if you ask me. The LED's state is solid red which clearly means (and the X65 system operation notes back this up) the key/code is not only being recieved but is being accepted just fine (if it were a code unknown issue or failure to recieve the code it would be flashing at 4Hz) and the immobiliser is remaining active because something system critical on the CANBus is failing to report in (this would be confirmed and most likely narrowed down to a specific node by running the network infrastructure tests in CLIP). It scares me that some Renault techs can't use the dealer level kit properly.
Honestly, in nearly 15yrs working on these cars I can count on one hand the number of genuine induction loop faults I've encountered. Check all your fuses first and then launch into some basic wiring conformity checks...
... Normal causes of wiring related issues are in the engine loom around the gearbox area or, if fuse related, the UCH fuse in the passenger dash fuse box or poor contacts in the engine bay fuse box to the three blade fuses in positions 1, 2 and 5.
Mick