You're welcome, anytime.
The lockers, you pick your own code and which ever locker you wish that is empty. It's very easy, instructions are on each locker. Workout facility, yes, in the same building. She will see it on the right side of the lobby when you enter the spa building. They give you a robe and slippers to wear to and from the services. There is, also available in the change room, tea, water and cookies or fruit.
What my husband did once was give me a package to open after I was done my services at the spa. It turned out to be my favorite dress, jewerly, and highheels, with a note that said. "put this one and meet me outside". He was standing there with roses, in a suit, looking fine. We walked over to Narcoosees for a romantic dinner (he made the reservations in advance). Fantastic end to a wonderful and special day. I hope you can do the same for your wife. It's those memories that make us feel special when our day to day lives are overwhelming.
Have a great vacation! Glad I could help.