The PsiElementFactory factory methods returns only PsiJavaCodeReferenceElement. PsiReferenceList does not have anything special to add reference except its super class PsiElement addXXX() methods that takes a PsiElement in parameter. Unfortunately PsiJavaCodeReferenceElement does not descend from PsiElement even though its name might indicate that.
So how do I add a reference to a PsiReferenceList now?
Sorry if I should not have asked PSI questions in this forum. I am somewhat confused where we left off this issue.