Welcome to the Core 🙂
Please upload the scene file with any questions like this so that we don't have to recreate your entire setup from scratch without knowing fully what it is !
I think that is going to be expected behaviour, because presumably the XPresso needs to calculate the specific distances of points in the one object it refers to, and all the cloner does is what it says on the tin, and clones that first object, so can't do anything different with the clones unless via effectors etc.
I am no XP expert myself, but I think you'd have to plug the Cloner output into the Xpresso somehow, and calculate the collision data for each and every clone.
CBR