It all depends on what exactly you want to do with this part of the code and what you expect the result. Your problem is that you never make a big description of what you want to do and what the script should do. Because of this, one has to guess and build theories, which leads to an unwillingness to guess other people's riddles without clearly stated conditions for solving a certain problem. If you could explain in more detail what you specifically want to do and what your code should check, then perhaps we would have found some other way to solve this problem, without resorting to the way that you are trying to use, and without trying untangle this tangle.

Also, you have a syntax error. The correct syntax and examples for "$iif" are described here:$iif or$iif

I can only guess, what you wanted to create something similar to this:
menu nicklist {
  Nick Status:{
    if ($$1 isop $chan) /echo -a $$1 - OP
    if ($$1 isvoice $chan) /echo -a $$1 - VOICE
    if ($$1 isreg $chan) /echo -a $$1 - USER

If you still have questions on this topic, please state them here in a more detailed and understandable form.

🌐 📜 6667 #Code (mIRC scripts, help, discuss, examples)