You could do SYD - AKL with (Air)NZ, joining in/putting in SQ KF FF#, which can be transferred to VFF later on, and then look at NZ8 from AKL - SFO, bypassing LAX, from there, can get something close to SMF/direct to SMF, if she wants to bypass LAX.
AKL is a very easy airport to transit.
Hearing the stories of LAX, if I were doing this, I would do the via NZ way, and SFO might be an easier airport to enter the US by.
There is an AirNZ codeshare, NZ9695, not sure if its UA or another airline.
Gives a bit of time to move the legs on the long odyssey to the US.
But wait till the others come in and see what they say.
Edit: Nzd$912 one way, AKL - SFO - SMF with UA 17Nov19.
Nzd$1213 one way, SMF - SFO - AKL with UA 02Dec19.
Both carry the NZ flight number, and both fares are whY, from the (Air)NZ website, it won't allow a straight booking on the website from SYD though.