Driver-enforced SSAO (Ambient Occlusion) no longer functions

Some time ago, I discovered it is no longer possible to force Nvidia driver-based SSAO onto Garry’s Mod through conventional means, and although some workarounds fixed this temporarily (locating hex values manually, for instance), for some reason none of them seem to work anymore.

Would it be possible to either A: determine what is causing Garry’s Mod’s hl2.exe to be flagged as incompatible in the Nvidia Control Panel, or B: determine what the new/altered hex values needed are to get the driver-level shader working again?

I do scenework in Garry’s Mod, and in-game SSAO saves me a considerable amount of post-processing time. I don’t think I can continue using it for this purpose if there is no feasible way to fix this issue, and I’d rather not have to learn SFM on short notice.