Anyone VERY familiar with NVFBC capture relative to desktop resolution

So ive been all around the world on this one. Problem has plagued me for a LONG time. Ive gone so far as emailing nvidia over it, and was told they arent going to waste their time as nvfbc is now considered deprecated. Whelp, until steam replaces it with a successor, its certainly not deprecated for steam link/steam link app users!

Ive been to the steam forums. the nvidia forums. reddit. ive googled until my eyes bled.

This forum is extraordinarily helpful when it comes to windows issues. It has no equal. Never thought to try here on this but ive got nothing to lose.

So i game remotely the overwhelming majority of the time. My main pc is two 4k displays.

Theyre only 27" so im forced to use windows scaling at 150%

If i stream to my tv with nvenc or hevc, all is well - I get 4k capture. If i stream via NVFBC, I get 1440p.

I can NOT figure it out. Windows scaling somehow for some reason is taken into account when capturing a full screen game (and yes ive tried borderless as well).

I have undid scaling on one of the displays, and it changes my capture resolution by half. Its absurd. I then end up with 3840x1440 and a stretched letterboxed image. If I disable scaling on both displays, I get the full 4k capture. I have entertained doing so as this is super important to me, but I just cant justify being miserable or unable to see or straining my eyes while working.

For now ive had to omit using nvfbc. Had i known this before investing in new displays, I likely woulda gone for bigger displays that I can run native 4k on without so much pain.

Anybody know why this is the case and if i have any means of fixing it?