The Cambridge Grammar of the English Language (Page 919):
8.1.2 Exclamative what
What occurs in NPs with a following noun head: there is no exclamative counterpart to the interrogative what of What did they bring with them?
Does that mean the exclamative what can only be used with a following noun head?
If so, what about this example from Oxford Dictionary?
(in exclamations) emphasizing something surprising or remarkable.
‘what some people do for a crust!’