Any intelligent and reasoned decision would require additional information regarding the quantity of larger prizes.
Since it is a "drawing", the odds can not be determined because the number of entries making the choice to "gamble" is unknown. The casino should be willing to furnish those asking with the number of top prizes available. Also the likely probability exists that top prizes will not be awarded/won.
As for the "right" way to play this promotion, IMO......
I would reschedule from Thursday arrival to Friday arrival so that my play day could overlap and allow me to double dip the promotion. THAT would be the only advantage play for something like this.
It ain't rocket science. Go Fri-Sat instead of Thurs - Fri and double you chance for the top prize, and get twice the free play.