CA Easytrieve is not designed to have "&" references in the MACRO definition, only in the body of the macro.
The Programming Guide identifies the following:
Within the body of a macro, the ampersand (&) is the prefix concatenated to parameter substitution words. You must spell parameter substitution words exactly the same their counterparts on the macro prototype, except for the leading ampersand.
The workaround is to hard code the "&" value where it is needed, instead of placing the "&" in the invocation of the macro.