HiDPI Resolutions 2560x1440p Unavailable?

I am trying to get 2560x1440p HiDPI resolution to work on my hackintosh but to no avail.

I have a i7 8700k running iGPU over DisplayPort to a LG 4k (3840x2160) UHD monitor. I am running High Sierra 10.13.4.

I have attempted these 3 guides:

https://comsysto.com/blog-post/force-hidpi-resolutions-for-dell-u2515h-monitor

https://www.tonymacx86.com/threads/guide-add-your-custom-retina-hidpi-resolution-for-your-desktop-display.102321/

https://forums.macrumors.com/threads/updated-turtorial-non-2x-custom-hidpi-mode-on-macs-fixed-mouse-delay-problem.1568657/

as well as RehabMan's guide which is similar to one of these above anyways ^

I have tried creating the required plist file which looks like this: https://imgur.com/qba4Veh

And then SwitchResX reports these in the custom resolutions tab: https://imgur.com/UWMPpIo

My System->Display preferences however never shows HiDPI options before even editing the plist files which its supposed to after running the sudo window server commands? See image here: https://imgur.com/7OUyY2j

I have disabled SIP as well. When I try to select the custom resolutions from SwitchRes X, the screen flickers from an image and black and then reverts back to the previous resolution (which at this time is 1080p 60hz). Can anyone help me out?