I think you're right because I hadn't connected the console with the save file with the injected raid mons to home yet, so that might explain why the older mons had their Height fixed and equal to their scale and the new test mons from injected raids had both Height and Weight variable.
Judging from the pictures and the explanation, do tera raid events naturally have variable Height and Weight, with the Height value getting changed to the Scale value (usually 128 for mons with the mightiest mark) whenever home is used on the console whereas Weight stays at its random value? Is that it?
Also, does that mean then that the variable Height and Weight from injected tera raids won't pose a legality issue?