Looking to the Renault technical advice it would appear that they have a
SPECIAL TOOLING REQUIRED
Ele. 1552 Windscreen wiper arm removing tool !
The drive pin on the underside of the rear window sits into the plastic drive hole groove in the tailgate. The tailgate contains the wiper drive motor. Check that the lock pin and groove are aligned correctly and that the rear wiper is also positioned correctly on the shaft splines when the motor is in the park position..
Something I just learnt...
If you put the car into reverse when you have the front wipers on..
The rear wiper will automatically start for you thus clearing any drops of to help you see..