For grouping profiles, MEMBERKEY holds the transaction names from MEMLST, so it is a repeated field and RETAIN has no grip on it.
For transaction profiles, MEMBERKEY is filled with the value from PROFILE.
Consequently, if you want to see the sum of profiles related to a CICS region CICSA, and it lists the grouping and members together, you would write
SELECT CLASS=%CICSTRN MEMBERKEY=CICSA.*
If you wanted to export the relevant profiles in a fully retained format, you can think about newlist type=racf_access, see https://www.ibm.com/docs/en/szs/3.1.0?topic=racf-access-connects-permits:
n type=racf_access nopage
select member_class=tcicstrn raclist_merge=yes
sortlist ,
member_class member_key(17),
class PROFILE(17),
id access id:name
Note, there is no need for RETAIN since each entry in this newlist has all the fields filled out. Also note the underscore in the field names, confusing if you used newlist type=racf before.
Finally, if you want to export to a spreadsheet, try replacing the NOPAGE keyword with HEADER=CSVT or HEADER=TSVT. You could also remove the overriding length (17) for this export since fields are automagically cropped.