> In P12 Box SPM.1.1, and P14 note 25 (explicitly), both state net zero for that date.

I believe you're misreading; from p.12 Box SPM.1.1:
>> "scenarios with very low and low GHG emissions and CO2 emissions declining to net zero around or after 2050, followed by varying levels of net negative CO2 emissions23 (SSP1-1.9 and SSP1-2.6), as illustrated in Figure SPM.4."

Both are net zero around or after 2050.

Similarly for p.14 Note 25:
>> "SSP1-1.9 and SSP1-2.6 are scenarios that start in 2015 and have very low and low GHG emissions, respectively, and CO2 emissions declining to net zero around or after 2050, followed by varying levels of net negative CO2 emissions."

Both locations clearly note that the scenario may reach net zero after 2050.

> I think you're looking at the CO2 output only graph, i suspect perhaps in aggregate they provide net zero for 2050.

None of the other GHG graphs reach net zero even by 2100, so net zero GHG emissions always occurs after net zero CO2 emissions.