Let's update our stock firmware preserving our fuses :
- Reboot your switch into the Hekate menu.
- Use the launch option to start your stock firware.
- Connect to the internet on the stock firmware.
- Download the update.
- Before starting the upgrade, insert the JIG into your switch.
- Start the update.
- Before it completes press the button
volume up ( + )to make sure that the system is going to reboot into recovery mode.
- The system will restart and enters into recovery mode.
With the steps above your stock firmware was updated and the fuses were not burnt.
You can now inject the payload and re-enable AUTORCM ( assuming that your switch is the exploitable one ) then launch your stock firmware from the Hekate menu or your emuMMC.