I think any normal russian tortoise will escape from that on the first day. They can climb like a lizard… almost… I think you need taller walls, and even better would be to make something with a lid on it.
I have to agree about the likelihood of your Russian getting out of that; they are great climbers. You will need something with shade or an underground hide/burrow in Las Vegas.
Agree with all the above. My Russian still gets out and he has a fence buried so he can't dig and very tall fencing. I caught him once climbing straight up a tree. Yours won't take time at all getting out of that. Also if it's an adult, should be a big space. Minimum of a 4x8 but outside should be bigger. Yours looks small unless it's just the pic.