@OP The AGM batteries are way better at "hanging on" (and seem to not self-discharge at all) if there is a parasitic draw so it would be best to measure the draw to make sure and not assume there isn't one especially if you suspect something is wrong.
If you don't already know, if letting the car sit for any length of time then maybe give the keyfob an extra push on the lock button immediately after the first push, the clown nose should give a long flash indicating the interior sonic sensor is disabled so less drain on the battery if it gets triggered (which you probably wouldn't even know because the alarm horn probably doesn't work!
) and what ever drain from the sensor it self.