Mesh Caustics Dispersion not working in Unreal Engine 4.26?

Hi I’m trying the MeshCausticsDispersion demo with the NvRTX 4.26.2-1 release branch but dispersion isn’t working, even when I increase it in the project. I can get it to work with 4.25 but there’s the DLSS overlay I can’t get rid of. Any reason why this isn’t working in 4.26?