Harrahs would have built the casinos, set everything up and then handed them over to Gala after a couple of years, after pocketing a hefty fee. They have done this very succesfully in places such as New Zealand and South Africa.
Harrah's role was to be in setting up 5 or 6 much larger casinos. This was when it was looking like the government was going to allow more 'supercasinos' and 'regional casinos' than the one currently proposed.
But I think if you backed the Stellers at -4.5 then unless you can find a match at +4.5 for the Dolphins then your best off sat at home with a beer shouting 'Go Steelers!'
The odds you will get on Miami at +4.5 will be poor, limiting your profit.