Might not be even the gearbox faulty. I think the owner masalah.
The diagnostic report only says the technician heard the sound comes from gearbox. Never even plug in ODB2 diagnostic tool , no fault code report from TCU.
I think it can even be the owner heard the infamous CVT whine when full throttle up Genting which is normal.
These days you cant even trust service center technicians. These newbies are paid low wages , you get low quality job

You should ask in F&F section. You come to /k and asked these kind of thing , you should expect ppl troll you.
Its like you go to a monastery asking for a comb .