I will just ask for help here, because I literally copied all the parameters in your mesh computation, and I am still getting the weird refinements. I can see that most of them are the same as mine, only difference refinement levels.
I am just scratching my head here, any detail in your findings is welcome.
Edit: I found something I had missed, it is running, will report back.
Edit 2: Fixed! Just for the record, the problem was the size of the refinement box for the meridian interface. Changing dimensions for it to be just smaller than the domain was the fix, thanks Sam!. I also now have two meshes, one coarse with ~500k cells and a finer one with ~3.8M cells.