This little bit of SQL should help you determine who created a table or when it was created…
SELECT
CASE TAB.TYPE
WHEN 'A' THEN 'Alias'
WHEN 'N' THEN 'Nickname'
WHEN 'S' THEN 'MQT'
WHEN 'T' THEN 'Table'
WHEN 'V' THEN 'View'
ELSE 'OTHER: '||TAB.TYPE
END AS T_TYPE
,RTRIM(TAB.TABSCHEMA)||'.'||TAB.TABNAME AS TABLE_NAME
,DATE(CREATE_TIME) AS CREATED
,DATE(ALTER_TIME) AS ALTERED
,TAB.COLCOUNT AS COLUMNS
,TAB.DEFINER AS CREATED_BY
FROM SYSCAT.TABLES TAB
WHERE TABSCHEMA = 'XX'
ORDER BY TABLE_NAME
FOR READ ONLY
WITH UR;</pre>