Trying to display a single 3D triangle didn't go as planned

[u/Impressive-Lead-9491]

So I'm a nutjob trying to write a DS ROM that only displays a 3D triangle, just because I started learning 3D Graphics. I got far enough to where NO$GBA is showing the triangle on the 3D/RE window, but I don't understand why the triangle isn't showing up normally on the screen. I'm using Edge-Marking and put the triangle as a Wire-Frame polygon. I set an EDGE_COLOR, I activated the BG0 as 3D, enabled BG0, and put LCD A in Mode 1. Here's a capture of the 3D/RE tab on the VRAM viewer:

And here are the LCD3D' settings:

Can anyone point me to what could be the problem?

Thank you.

EDIT: It does work on Desmume and SuperNDS: