There has been significant success.
1. The flaw has been eliminated.
2. Clear ice with bubbles. No giant white flaw. Ice spheres look like the glass ornament on your grandma's fancy table.
Not perfect but I think I'm really close.
16oz double walled plastic glass
1/2 cup plastic container (ziplock or rubbermaid)
the ice mould
Fill both mould and 1/2 cup container to brim with water. I used RO. Upend mould into full container leaving it at a slight angle. You don't want the hole in the mould facing directly down but offset a little.
This cup holding the mould is placed into the opening of the double-walled cup. Place this into the freezer.
Ideally all the water in the mould will freeze and push the gasses and impurities away into the unfrozen water in the 1/2 cup container which will also slightly freeze.
I got real close without having to use the suspended and partially submerged perforated icetray in a cooler in the freezer method.