OK, cross posting, as I see you did post your EA. So, reading the group membership from the admin group is unfortunately not going to be 100% accurate. The reason is that if an account is deleted, it doesn't always get removed from the admin group's GroupMembership. What might be better is to use a combination of reading the admin group and checking to see if those accounts actually exist, and only if they are still present, add them into an array, and print the array at the end.
Example:
#!/bin/bash
admins=$(dscl . -read /Groups/admin GroupMembership | tr " " "
" | grep -v "GroupMembership:" | egrep -v "root|_sophos|_mbsetupuser|_jss|casper")
while read USER; do
if [[ $(dscl . read /Users/$USER 2>&1>/dev/null; echo $?) == 0 ]]; then
adminsArr+=("$USER")
fi
done < <(printf '%s
' "$admins")
echo "<result>$(printf '%s
' "${adminsArr[@]}")</result>"
This takes the result of checking the admin GroupMembership, minus the accounts you want to exclude, and then checks to see if dscl is able to read each account record without an error. If so, it adds that account into a new array and after exiting the loop, prints that final admin array as the result.
On my own Mac, I have one or two temp accounts I had once created that I then deleted, and unfortunately these still show up in the admin GroupMembership. It likely has to do with how the accounts were deleted. I assume if they get deleted from System Preferences, it cleans up the admin group membership. If they are deleted from the command line in some ways, it may not. sysadminctl probably cleans up the membership though.
