Download and play. They have multiple games that can all link to the same account. Depending on phone type (Iphone vs Android) one has limited amount of LP (loyalty points) they can accrue daily. Since you have only a month you would have to play obsessively on all platforms including Facebook to build enough LP, but it's doable. You and your wife could build enough to get 1 free night each. There is MyVegas slots,, MyVegas slots on FB, MyVegas Black Jack, Konami Slots, Pop Slots and I think more. I haven't played for a while... Download all, play all, collect all and really build those LP's.
I would join the MyVegas FB groups. You can get free chips daily and there are usually sites that give away free play chips. You can also purchase small amounts if you don't mind spending a couple of bucks or more. Sometimes this helps people see the 2-day free room awards as you will likely only see 1-day free nights. People will use like Google Opinions to get free PlayStore credit and use that free money to pay for MyVegas play chips. I never once paid, but my wife and I use to play it over 8 years ago. Free rooms are usually only weekday nights (Sunday-Thursday) though, but sometimes they will have Friday's for the lower tier hotels. In MyVegas all hotels are MGM resorts.