OP: just because you have a 4Q score for Casper does not mean you will score 7+ (4Q) on PREview. They are different exams.
Do you know if your schools require an additional SJT or virtual assessment like Kira Talent (UCI) or SVI (WUSTL)?
I can give you the admissions pitch that they will find good students with mission fit. Many do, but PREview or SJT are still under investigation at many schools. There is some relationship with student success, but those results have not been published. Nor are they definitive.
If these schools were strong mission fits for you, you should have picked them earlier on. But we are near the end of August. Either you are panicking early because your list has not given you IIs, or you are not satisfied with your schools that have and don't really want to practice interviewing (which you should be starting now).
It sounds like you are thoughtful and deliberate with your process. I cannot tell you what you should do... it's your call and your budget to submit these additional secondaries and prepare for PREview. I just want to be sure there are no additional surprises that will put you under more stress.
I still stand by my advice to treat a required PREview like you would an MCAT. Would you take it in September?