...ok. So how about this:
* The casino has an advanced security system with a series of timelocks, but we know from the disgruntled designer of the locks that they don't react well to leap-second changes,
* The guards are mostly recruited from the same native tribe, which would normally rule out placing our own candidate in the main security room, but luckily the local customs only require one parent to already be of the tribe to make one ellegible,
* All the gold in the vaults is always temporarily enchanted by leprechauns, so that if it is removed without authorisation it will evaporate by morning, though they obviously have to outsource this work,
* There's a great big slicey pendulum across the main access corridor, for some reason... it's huge!
* Dogs. Manning the casino's check-in desk. Strange but true, and apparently something to do with the scent of every guest being checked out automatically, as the dogs operate the credit-card readers and then fetch them their keycards,
* All the air-ducts we can use are vertical and have completely smooth, near frictionless surfaces, with no place to fix ropes or cables,
* Infrared cameras.
The solution to all this is then obvious:
* We'll take advantage of the doppler effect as much as possible, by going so fast that they won't see us coming,
* We shall push the casino onto its side at the crucial moment, obviously,
* Woof, woof woof, woof woof HOWL woof, pant-pant-pant. Woof <sniff>, woof <lick>, woof <scratch behind ear with hind leg>, whimper grrrrr! Woof pant-pant <paw>. "Good dog!"... Or something similar, according to the circumstances on the day, but you get the woof idea,
* Dancing lessons for all! Just gotta develop a bit of rhythm, and no risk of the slice-and-dice from the slow swing of the pendulum,
* I got a weather-controller cheap on the black market. Rain on demand + sun on demand = rainbows on demand = leverage over the little green-clad guys,
* Send our most virile member of the team to wine and dine a number of the local girls... Some time later, we'll have our pick of offspring to recruit to our task and then get enrolled at the casino,
* Affix giant horizontally-facing rockets to the planets equator, such that we can slow its rotation down at will.