You should be able to stay in any Caesars property (Harrah's, Paris, Cromwell, Planet Hollywood etc.) OR eat at any Caesars property restaurant (Giada's Gordon Ramsay, Bugsy and Meyers etc.) give them your Diamond card, along with your credit card, and/or charge to your room, and spend $100+ to earn 100 tier credits.

The only issue is that the terms state it can take 7-10 days from checkout or purchase to get the tier credits applied to your account. This is fine if you make multiple trips to Vegas per year, but could be an issue if you have a short stay.

Tier credits earned from gambling are applied to your account immediately--if slots or very quickly if playing a table game, so you may be able to visit the Caesars Rewards desk and/or a casino manager, after showing them that you have earned 100 tier credits, to get them to manually add it if needed. Good Luck.