While I've never used
intersect_ray(), the docs mention a number of ways that objects can be ignored by the raycast. I'd assume one of them can be made to work for your case...
Additionally, the method can take an exclude array of objects or RIDs that are to be excluded from collisions, a collision_mask bitmask representing the physics layers to check in, or booleans to determine if the ray should collide with PhysicsBodys or Areas, respectively.
I'm not aware of any way to specifically ignore one-way collisions using
Docs are here: