'Just 2 teachers', with an ocean view, and is that a pool? LOL
How are your rear surrounds wired? Pre-construction, or wireless?
That video is worth 1000 words, worth the effort.
What's on the other side of the wall where you want to put the right speaker? Seems kind of high, but you gotta do what you gotta do, sometimes.
If you hung the TV on the wall with an articulating mount, you could use attached L-R speakers, and even a center below. I don't know how to attach anything to that stucco wall - wood studs behind?
How about locating the L-R speakers lower - R on that low knee wall, and the left on-wall, at the same height?
Uh, what's a 'corner type mount'? This?
You could also consider articulating mounts like these
Dedicated 'corner mount' not required to mount a TV in/near a corner. You could move the TV up on the wall, with plenty of room for a sound bar or center channel below. You could even move the whole TV up above the knee wall, and get that 80" TV.