Rock 4C+ v1.4 + PoE + Radxa 8HD

I’m putting together a project and I think there’s some incompatibility with my chosen hardware.

Rock 4C+ v1.4 with a PoE Hat
Radxa 8 inch HD display
(I’m using rock-4c-plus_debian_bullseye_kde_b55.img but I don’t think it matters here.)

The hardware is all connected and working when powered by USB C. When the board is powered from the PoE port, the display does not turn on, but the system is fully powered on as seen on the TTL.

I’m aware of the available board diagrams but I do not understand enough to know if any voltage is sent to the MIPI port when the board is powered through PoE.

Would this be something that can be changed in the DTB/DTS? Or is this not a compatible set of hardware?