Thanks. I see your RESIZER bone has an 1-bone IK constraint so it points at its parent bone, CTRL_POSITION. The RESIZER bone is positioned at local translation 0.0055,0.0101, which is very close to the parent (0,0 would be on top of the parent). This makes the IK constraint very sensitive, the smallest movement of the RESIZER bone will rotate it a lot so it points at its parent. When you export to JSON, the translation values are rounded to 0.01,0.01. When it is reimported, the small movement to the RESIZER bone causes the IK constraint to rotate it by a lot.
JSON export rounds the translation to make the data easier to read. We could give it more precision, but it doesn't usually matter and I'd guess you'll want to adjust your rigging so translation of the RESIZER bone is not so sensitive.
I didn't find any other problems with exporting, changing the clipping attachment vertices to be exactly on whole numbers, importing, and exporting again. The whole numbers were kept when doing this.
