As an FYI for those who may hit a jackpot after the tables and cashier cage are closed they have a form you fill out by the cashier cage. You fill the form out and drop it in the box. When the casino opens up in the morning they will load the jackpot onto your cabin card.
There's many a night I am still playing the slot machines til 5am in the morning. But you were on the Zaandam. Not exactly one of HAL's busier casino ships.
I understand now, I do not remember where I got that from but it was not my invoice. Both my wife and I receive offers of a Neptune Suite from the casino and we have for years. All the way back to 2007.
I always stay in aft wrap neptune suite. I have never stayed in any cabin other than a Neptune Suite so I can not help you with a Signature Suite question.
If you could tell me exactly what the offer was I could probably get you the code. I would need to find someone with the same offer and find out what their code was. Not easy but I may be able to pull it off.
This is hit and miss. Many times it does show up on your cabin card. It all depends whether the hosts have enough time to get the free play loaded. Personally I like to use my free play on the tables so I get free play chips at the cage.