@leo-dabus almost got it right. For the above example where values is defined as:

let values = ["VAL1", "VAL2", "VAL3"]

converting the array to a CVarArg argument should be defined as:

let cVarArgValues = values as [CVarArg]

which will give you cVarArgValues in the desired format of 3 distinct values in a single array; ["VAL1", "VAL2", "VAL3"].

If you don't wrap CVarArg in [], you'll get a valid, albeit incorrect, argument list consisting of a single-value array wrapping values as an inner array; [["VAL1", "VAL2", "VAL3"]].