Could you please tell me if the following sentence is correct?
A. Will Sue be going with you to New York?
B. She wishes she ...came...(come), but unfortunately she's very busy at the moment.
Here I am asking if came can be used rather than could/would come.
No, "came" cannot be used in that example. "Came" is simple past and A. is asking about B.'s travel in the future. "Could" with "wishes" is correct.