The US judges didn't ding Caroline for her flutz or URs in her FS. I'm not so sure the ISU judges will be as kind. And there's one less spin in a Junior FS, so that will cut down on her +GOE.
Meanwhile, Rachael and Mirai were well-treated in the JGP this year.
Actually, Caroline did get 2 flutz dings in the FS, and it's true that she got no UR in the FS, but then she had no UR's in the GPF LP either except for the last 3Lz she fell on. The National's LP was certainly the best LP she skated all year, so it makes sense there were no downgrades. Also, junior int'l judges are more lenient than senior ones in general, so if she got by the senior judges (except for the draconian ones at SA) then I think she will be okay at JW with the same quality of jumps.
It is actually Rachael and Mirai who got multiple edge (Rachael) and downgrade (Mirai) deductions on the JGP, and who were treated very kindly at National's. Also, Rachael & Mirai's PCS went way up compared to JGP's, and Caroline's was on par with her GPF PCS. Obviously senior PCS tend to be higher than junior PCS, but last year Caroline got higher PCS than Mirai, and this year Mirai got way better PCS than Rachael on the JGP (a difference that was minimized at National's). So it would be very interesting to see how they all get scored together by the JW judges.
I think with totally clean SP's including ratified 3-3's, Mirai & Caroline will be really close, and Rachael would be about 3-5 points behind, mainly due to lower levels/GOEs on spins/spirals/footwork, as well as lower PCS. Also, Rachael never had her 3-3 ratified in the SP by international judges, so it will be interesting to see if she gets it at JW. Mirai, of course, never tried 3-3's before National's, and was downgraded in the LP.
As for the LP, if everyone skates totally clean, I feel like Mirai should be slightly ahead of Caroline though quite close, and Rachael should be further behind -- again because of higher levels/GOEs Mirai/Caroline get on the spins and spirals, and also higher PCS. But on the other hand, Rachael & Caroline have had a good track record of having their 3-3's ratified in the LP, whereas Mirai doesn't. On the other hand Rachael get occasional edge deductions, Caroline get frequent ones, so that evens things out a little.
I think a lot just depends on how well each girl skates on the day of the competition, as well as how strict/lenient/consistent the tech panel is.