Octavia 4 COMBI (2020) tailgate lock stuck

My Central Locking will not open the tailgate on my Octavia 4 Combi. I have accessed the internal manual opening latch through a very small hole on the internal side. Once opened I have sprayed in PTFE spray (maximum lubrication/minimal dust attraction). This has restored the remote locking function. Today’s heavy rain has brought the issue on again. I really need to get at the actuator mechanism to lubricate/prevent moisture ingress. I can not find a way of getting at the part.

To go further than spraying broadly into a small hole in front of the mechanism I want to get to it properly. Does anyone knowhow to get at this part on the tailgate?