How difficult is fixing a T3 CNRB Timing Cover Leak?

So my '13 T3 has been leaking a small amount of oil for quite a while (about 300 mL per 4000 miles, some appears to be leaking out of the timing cover while some has ended up in the intercooler). I'm trying to determine how difficult it is to correctly fix the timing cover leak so it doesn't leak for at least another 100K miles.

The vehicle has 154K on it now and the dealer performed the "oil pan oil leak campaign" at around 100K miles. This apparently involved stripping the engine down to the long block and removing all oil covers including the timing covers. The driver side timing cover on the head or at the head to block timing cover junction appears to be leaking (can be seen from under the car).

I've heard this repair can be performed by removing the transmission, however it is more difficult to do with the engine in the vehicle. I'd rather not remove the engine if I don't have to, to fix this. At the moment I have access to a 2 post lift so I could probably remove the transmission to access it. However I'm trying to understand what sort of headache this will be and also if anyone has ever gotten the timing cover resealed and last a more than 50K miles.

Thanks in advance.