Ultraman

If I were you, I will ask them directly:
1. You said  "我地今日冇金菇牛肉卷，今日冇金菇，所以做唔到" But how come there is 金菇 in my 雜菌 order?
2. Is that not enough 金菇 to make the 金菇牛肉卷 but just good for 雜菌? (I experienced I couldn't order a toro sashimi but a negitoro maki instead.)
3. "我好似前排叫過。": are yourself sure that you had ordered that not long ago (within the 2 years time)? If you can't even be sure yourself, it's very difficult to have a strong stand point /proof to argue.
4. Just challenge them: "Oh, since the menu hasn't been updated for 5 years, please tell me what other stuff is not being carried anymore? Or are you telling us that we should go to another better restaurant?"

And yes, I also like to know which restaurant is it please?