Pixel Fold won't go into folded mode

I recently bought myself a pixel fold that presented itself with an issue I've never seen before- the phone works mostly fine, however the phone always acts like it's in the open position. I've been looking into the issue, and have narrowed the issue down to either the lower sub board or the hinge flex cable, however I'd like a second opinion before going forward with a repair. Here are the symptoms:

-Phone will not enter closed state, and doesn't adjust content when the phone is flexed

-"Hinge Angle Sensor" doesn't report any data in Castro diagnostic app

-Accelerometer 2 and Gyroscope 2 (both located on lower sub board) don't return any diagnostic data in the Pixel diagnostics app

-Booting takes multiple minutes, and the phone sometimes boot loops for a bit before successfully booting (however once booted, the phone works normally without any random reboots or shutdowns)

-When attempting to use dual screen features (like made you look, picture previews, or the translate feature), the phone says it has started the feature, however it becomes extremely laggy and starts warming up

With all of this, I would also like to point out some other things that are tossing me up

-The issue is persistent and is never not present. The previous owner also said that the issue just began one day with no build up or intermittency

-The outer display is functional, it is able to display picture during boot and when charging while powered down

-The phone can read SIM cards consistently (sim reader is on lower sub board)

-Battery life is normal and consistent, so the larger battery is able to make a proper connection with the mainboard

So to ask, is it more likely that the flex cable or the lower sub board is at fault? Any help would be greatly appreciated