I see you tried doing this by creating a new array item:
echo "WAJA[".$n."][".$m."][1] = "."'".WA_DD_Replace($row_officesulist["musufirstname"])."'".";\n";
echo "WAJA[".$n."][".$m."][2] = "."'".WA_DD_Replace($row_officesulist["musususurname"])."'".";\n";
instead of creating a new array item, concatenate the last name into the original array item:
echo "WAJA[".$n."][".$m."][1] = "."'".WA_DD_Replace($row_officesulist["musufirstname"])." ".WA_DD_Replace($row_officesulist["musususurname"]."'".";\n";