Question for you since you know a lot. Is it ok to get eye work (fillers or even canthoplasty) prior to jaw surgery?
Filler is definitely fine.
I'm not a doctor (so take this with a grain of salt), but I'd be slightly hesitant with the canthoplasty (especially if there is any lower eyelid retraction work done) if you're going to have an upper jaw movement later, for a couple of reasons.
1) Maxillary advancement has been shown to affect lower eyelid position.
2) Maxillary advancements often leave the upper midface relatively deficient. However, according to Dr. Taban (prominent occuloplastic surgeon), cheek/infraorbital implant placement after his almond eye surgery (which is canthoplasty + lower retraction surgery -- it might be different if it's just canthoplasty) is contraindicated, even if they're placed intraorally. So for some reason if you wanted implants post jaw surgery, it wouldn't be advised; you'd be forced to go with filler or fat (not saying that these are bad options, but you would have less options).
Not sure if this logic applies if you're doing a canthoplasty without any lower eyelid work.