It would absolutely not be possible to arrive unannounced. You are assigned a specific landing slot. We are not talking about landing a Piper Cub at an uncontrolled airport.
You’re assuming that that the 100% muslim Maldives would be unable to get any one else in on the scheme.
How many schemers would be necessary to pull this off at 4am in a tourist trap? If you’re the one who schedules work details, just make sure everyone working the night shift is loyal to the ‘cause’.
BTW, I think a landing at Banda Aceh is more likely. Assuming the 2000g extra fuel the captain requested according to some sources isn’t true.
If it IS true then a refueling stop wouldn’t have been necessary to get to Iran, Afghanistan or any of the other stans.