Asus Laptop can go to sleep, but wakes to black screen - not sure what else to try

[system information at bottom of post]

I've got most things working on my laptop (sound, graphics acceleration, keyboard backlight and function keys, workaround for no wifi), but the last issue I can't seem to figure out is one where it can go to sleep fine (or so it seems), but then when I wake it up it gets stuck on a black screen. Sometimes hitting a key on the keyboard will cause the backlight to come on, but it doesn't actually display anything and I can't tell if it's responding and just not showing the screen, or if it kernel-panicked or something.

I've tried various things from various sources but none have been able to fix the issue; the closest I got to one of them doing anything different was I got it to kernel-panic trying to go to sleep, rather than after waking it lol. Those things include device property injections in clover generated with the Intel FBPatcher.app, EDID injecting with the DisplayProductId- folder and DisplayMergeNub.kext (not at the same time) (I'm going to try it again though but with the EDID dumped from within Windows instead of using FixEDID.app), different system definitions (MacbookPro12,1 and MacbookAir7,2 appear to be the closest to my laptop's configuration), various SSDT files (though I admit I don't fully know what I'm doing in terms of ACPI stuff), various combinations of those things, ... nada.

Besides this one issue, everything else seems to be working normally. For the most part, anyway: today it decided it wasn't going to boot, which I fixed by rebuilding the kernel cache from within the Recovery OS; the culprit there according to the error report seems to be related to the PS2 kext, but that's a separate issue. And strangely, I've checked the Console for anything related to crashes or panics when it goes to and wakes from sleep, and can never seem to find anything that would be useful.

Any ideas of what I should try next, or what additional information would help lead to a solution?

Computer: * ASUS K501LX laptop * Intel Core i5-5200U / Intel HD Graphics 5500 * macOS High Sierra 10.13.6 / MacbookAir7,2 system definition

kexts in LE: * ACPIBatteryManager * AppleALC * ApplePS2SmartTouchpad * AsusNBFnKeys * CodecCommander * Lilu * WhateverGreen