The error message is due to the expression for V1, which is non-convex.
Have you proven that F1, F2, F3, F4 are either convex or concave? If YUW, YUZ, YEZ, YUZ, YEW, YEZ are all hermitian semidefinite, then the arguments of trace can be rewritten in terms of norm (…, ‘fro’), and would be convex and could be entered as such into CVX. But taking the log would be log(convex), which is not allowed by CVX’s DCP rules.