Evan
The electrical connection for Nextion is powered by a separate regulator and only for it. (An other addon)
see red circle on picture
We don’t see the PCB other side, but there’s also the resistor, capacitor, self.
Like you can see here
https://ubitx.net/2019/08/03/nextion-noise-in-rx/

Eventually, the only error would be that I put the resistance on the regulator input (+12). Should it be moved to the regulator outlet? (+5v).  It seemed more logical to me like that. However, I should add a small radiator, because it is quite hot.
cdt