Here's my 2 cents... I'd also not go the "Indian Guru" route, perhaps IMHO your overthinking this.
You are getting paid for this right?
If so... I'd get access (with all the required permissions) to a casino venue. Preferably when closed to the punters, so you can take your time and get the images you need without upsetting folk.
Photograph only the things people first think of when they hear the word casino. It's for online promotional usage, so you've only about three seconds or so when people first click on the site to hold the attention of the site visitor.
The images therefore must be visually fast, very colourful and eye catching, conveying immediately what they are, otherwise folk will click off to another site.
So I would treat this assignment as full commercial product shoot, meaning well lit, super sharp with clean backgrounds, with perhaps maybe just a few soft bokeh ish backgrounds of a casino environment to give a sense of place.
My suggestions to you as to the type of shots required would be... I'd get in real tight (macro lens?) and close, low angle, a visually striking different viewpoint... of say a roulette wheel, card shoe, craps table and the like.
Good luck and let us know how you get on.