You were asking if this CUDA compatability layer might hold any advantage over HIP (e.g. for use by llama.cpp) ?
I think the answer is no, since HIP includes pretty full-featured support for many of the higher level CUDA-based APIs (cuDNN, cuBLAS, etc), while per the Phoronix article ZLUDA only (currently) has minimal support for them.
I wouldn't expect ZLUDA to provide any performance benefit over HIP either, since on AMD hardware HIP is just a pass-thru to MIOpen (AMD's equivalent to cuDNN), rocBLAS, etc.