How to override IgnoreLayerCollision with IgnoreCollision?

Hi everyone,

It seems IgnoreLayerCollision overrides IgnoreCollision, and I am in a situation where I need the later to override the earlier:
Because I am not happy with Physx, the tweaked collider needs to ignore everything, so I call IgnoreLayerCollision with every layer. I use another collider as trigger to detect what object need to collide, and then call IgnoreCollision to allow collision between those two. I use trigger because it is smoother than collision, doesn't interfere with physics engine. But it doesn't work because it seems IgnoreLayer has higher priority than IgnoreCollision

Any help and suggest?

Regards