I had the same problem. It was my first event i have participated on stake.
When i asked today, why i didn't get the 100 dollar for doing all the missions, the support told me i am excluded from the event. Excluded after i done the missions. Really trustful casino.
I could understand if they do that with customers which only try to claim extra money, but i invest only this year more 50k dollars in this freaking Casino.
I will invest no more money on stake and wright about my experiences on every platform i know. For me it is more valuable thsn your dirty 100 dollars.