If it was an online contest, it would differ in many ways from the Hilton.
The Hilton contest is run by a Vegas based licensed Sporstbook, and entrance fees and weekly selections must be done in person, albeit local "proxies" can be utilized.
A contest that has the kind of payout plan you are proposing would have to be run by an off shore book. A US based website could not run it. It would be difficult for a US-based website to even promote it under the current climate.
If an off shore book did sponsor it, they would have to make sure that the actual plays of the contestants are posted for all to see, a reasonable amount of time before the kick off of the first game on the weekly schedule.(That's a particular problem with Arena FB, with the games spread out over several days, selections would have to be posted early in the week, cutting down on the amount of time you have to research your plays, since you also have to wait for the last game of the current week to be played, plus maybe a day for the opening line to settle down a bit before posting the "contest line.")
The sponsoring offshore book should be able to pay out 100% of all monies bet, since they have no risk plus get to sit on the money for the whole season.
If the contest was successful, they should even sweetin' the pot, since they would be getting lots of extra visits to their site from people visiting the site to see the weekly selections and results of the contestants.
Without the display of the selections in advance, any contest is suspect.
That's the problem with all those monitoring sites out there.
I wonder if there is one off-shore book that would garner enough entrants to make this a "real" national contest like the Hilton's is for Las Vegas.