its a shame you are so far away, I like a challenge.
Start by taking fuses out of non essential items to see if you are still having drain issues
This certainly would be a challenge
I'm just going to leave it tbh as I use the car daily anyways, so car never has a chance to die
I might get it looked into at a later date.
You or your mechanic need to put a multimeter with at least a 10 amp capacity on the battery earth terminal and then onto the battery (battery disconnected) so all the cars power goes through the multimeter, DO NOT ATTEMPT TO START THE CAR LIKE THIS! Then you observe the drain with the drivers door lock flicked over to simulate the door being locked. Then remove each fuse from the under bonnet fuse box and then the dash side fuse box one at a time until the excessive drain goes away. Make a note of the fuse number and post it on here so Someone can help.
The quiescent current should drop to around 0.060amps after 25 minutes before that time it could typically be around 1 amp max for very short time then variable - the reading after the 20 minutes is the important one as thats the one which shows the car has moved into a state of sleep.
If the sleep state is achieved the battery or charging circuits are the issue!