SQL & PL/SQL

Hello expert, Please I need your help to union results of two WITH Clause queries. The original query was a select from a union of two queries but the performance was terrible, therefore I decided to use a With Clause and the performance was good. But I stated getting syntax error  below when I tried to UNION the two with Clause queries.

ORA-00933: SQL command not properly ended

00933. 00000 -  "SQL command not properly ended"

*Cause:   

*Action:

Error at Line: 1 Column: 7,103

WITH 
QRY1 AS
(SELECT
      TO_CHAR(SYSDATE,'DD/MM/YYYY HH24:MI:SS') DATE_LAST_UPDATED,
      SXS_GAU.Y_DTT_HISTORY.PAP_ERA,
      SXS_GAU.Y_DTT_HISTORY.ACCOUNT_NUMBER, 
      SXS_GAU.Y_DTT_HISTORY.PAC_FSAH, 
      SXS_GAU.Y_DTT_HISTORY.PAC_STEP, 
      SXS_GAU.Y_DTT_HISTORY.WPE_JOB,
      SRS_PAC.PAC_PCCT,
      SXS_GAU.Y_DTT_HISTORY.DTD_COURSE, 
      PASS_FAIL_DATE.MAX_PASS_FAIL_DATETIME
      FROM SXS_GAU.Y_DTT_HISTORY
         JOIN SRS_PAC
              ON SXS_GAU.Y_DTT_HISTORY.PAP_ERA=SRS_PAC.PAC_NOTY
              AND SXS_GAU.Y_DTT_HISTORY.ACCOUNT_NUMBER=SRS_PAC.PAC_NO
              AND SXS_GAU.Y_DTT_HISTORY.PAC_FSAH=SRS_PAC.PAC_FSAH
              AND SXS_GAU.Y_DTT_HISTORY.PAC_STEP=SRS_PAC.PAC_STEP
         JOIN (SELECT PAP_ERA, ACCOUNT_NUMBER, PAC_FSAH, PAC_STEP, WPE_JOB, MAX(CREATED_TIMESTAMP) AS MAX_PASS_FAIL_DATETIME
              FROM SXS_GAU.Y_DTT_HISTORY WHERE DTD_COURSE IN ('PASS', 'FAIL') GROUP BY PAP_ERA, ACCOUNT_NUMBER, PAC_FSAH, PAC_STEP, WPE_JOB) PASS_FAIL_DATE 
                  ON SXS_GAU.Y_DTT_HISTORY.PAP_ERA=PASS_FAIL_DATE.PAP_ERA 
                  AND SXS_GAU.Y_DTT_HISTORY.ACCOUNT_NUMBER=PASS_FAIL_DATE.ACCOUNT_NUMBER
                  AND SXS_GAU.Y_DTT_HISTORY.PAC_FSAH=PASS_FAIL_DATE.PAC_FSAH
                  AND SXS_GAU.Y_DTT_HISTORY.PAC_STEP=PASS_FAIL_DATE.PAC_STEP
                  AND SXS_GAU.Y_DTT_HISTORY.WPE_JOB=PASS_FAIL_DATE.WPE_JOB
                  AND SXS_GAU.Y_DTT_HISTORY.CREATED_TIMESTAMP=PASS_FAIL_DATE.MAX_PASS_FAIL_DATETIME
      WHERE SXS_GAU.Y_DTT_HISTORY.PAP_ERA IN ('2013', '2014', '2015','2016')
      AND SXS_GAU.Y_DTT_HISTORY.DTD_COURSE <> 'PS OVERRIDDEN'
      AND PAC_AESC = 'U' 
      AND PAC_CLYN = 'N'
      AND PAC_STAC NOT LIKE 'Z%' 
      AND PAC_BLOK IN ('1','0')
      AND PAC_YEAR IN ('16/17')
      AND PAC_NOTY <> '2017'
      AND CASE WHEN SUBSTR(PAC_YEAR,1,2) = SUBSTR(PAC_NOTY,3,2) THEN 'N' ELSE 'Y' END = 'N' ),
 QRY2 AS
     ( SELECT
      TO_CHAR(SYSDATE,'DD/MM/YYYY HH24:MI:SS') DATE_LAST_UPDATED,
      SXS_GAU.Y_DTT_HISTORY.PAP_ERA,
      SXS_GAU.Y_DTT_HISTORY.ACCOUNT_NUMBER,
      SXS_GAU.Y_DTT_HISTORY.PAC_FSAH,
      SXS_GAU.Y_DTT_HISTORY.PAC_STEP,
      SXS_GAU.Y_DTT_HISTORY.WPE_JOB,
      CAST(RST.RST_MAS_PAC_HISTORY.PAC_PCCT AS NVARCHAR2(4)) AS PAC_PCCT,
      SXS_GAU.Y_DTT_HISTORY.DTD_COURSE,
      PASS_FAIL_DATE.MAX_PASS_FAIL_DATETIME,
      FROM SXS_GAU.Y_DTT_HISTORY
         JOIN RST.RST_MAS_PAC_HISTORY@PROD
              ON SXS_GAU.Y_DTT_HISTORY.PAP_ERA=RST.RST_MAS_PAC_HISTORY.PAC_NOTY
              AND SXS_GAU.Y_DTT_HISTORY.ACCOUNT_NUMBER=RST.RST_MAS_PAC_HISTORY.PAC_NO
              AND SXS_GAU.Y_DTT_HISTORY.PAC_FSAH=RST.RST_MAS_PAC_HISTORY.PAC_FSAH
              AND SXS_GAU.Y_DTT_HISTORY.PAC_STEP=RST.RST_MAS_PAC_HISTORY.PAC_STEP
         JOIN (SELECT PAP_ERA, ACCOUNT_NUMBER, PAC_FSAH, PAC_STEP, WPE_JOB, MAX(CREATED_TIMESTAMP) AS MAX_PASS_FAIL_DATETIME
              FROM SXS_GAU.Y_DTT_HISTORY WHERE DTD_COURSE IN ('PASS', 'FAIL') GROUP BY PAP_ERA, ACCOUNT_NUMBER, PAC_FSAH, PAC_STEP, WPE_JOB) PASS_FAIL_DATE 
                  ON SXS_GAU.Y_DTT_HISTORY.PAP_ERA=PASS_FAIL_DATE.PAP_ERA 
                  AND SXS_GAU.Y_DTT_HISTORY.ACCOUNT_NUMBER=PASS_FAIL_DATE.ACCOUNT_NUMBER
                  AND SXS_GAU.Y_DTT_HISTORY.PAC_FSAH=PASS_FAIL_DATE.PAC_FSAH
                  AND SXS_GAU.Y_DTT_HISTORY.PAC_STEP=PASS_FAIL_DATE.PAC_STEP
                  AND SXS_GAU.Y_DTT_HISTORY.WPE_JOB=PASS_FAIL_DATE.WPE_JOB
                  AND SXS_GAU.Y_DTT_HISTORY.CREATED_TIMESTAMP=PASS_FAIL_DATE.MAX_PASS_FAIL_DATETIME
       WHERE SXS_GAU.Y_DTT_HISTORY.PAP_ERA IN ('2013', '2014', '2015','2016')
      AND SXS_GAU.Y_DTT_HISTORY.DTD_COURSE <> 'PS OVERRIDDEN'
      AND PAC_AESC = 'U' 
      AND PAC_CLYN = 'N'
      AND PAC_STAC NOT LIKE 'Z%' 
      AND PAC_BLOK IN ('1','0')
      AND PAC_YEAR IN ('13/14','14/15','15/16')
      AND CASE WHEN SUBSTR(PAC_YEAR,1,2) = SUBSTR(PAC_NOTY,3,2) THEN 'N' ELSE 'Y' END = 'N')
SELECT PAP_ERA,
PAC_PCCT,
WPE_JOB,
SUM(DECODE(DTD_COURSE,'FAIL',SCORED_TO_DATE,0)) AS "FAIL_TO_DATE",
SUM(DECODE(DTD_COURSE,'PASS',SCORED_TO_DATE,0)) AS "PASS_TO_DATE",
SUM(DECODE(DTD_COURSE,'FAIL',SCORED_FUTURE,0)) AS "FAIL_FUTURE",
SUM(DECODE(DTD_COURSE,'PASS',SCORED_FUTURE,0)) AS "PASS_FUTURE",
SUM(SCORED_TO_DATE) AS SCORED_TO_DATE
FROM QRY1
UNION
SELECT PAP_ERA,PAC_PCCT,
WPE_JOB,
SUM(DECODE(DTD_COURSE,'FAIL',SCORED_TO_DATE,0)) AS "FAIL_TO_DATE",
SUM(DECODE(DTD_COURSE,'PASS',SCORED_TO_DATE,0)) AS "PASS_TO_DATE",
SUM(DECODE(DTD_COURSE,'FAIL',SCORED_FUTURE,0)) AS "FAIL_FUTURE",
SUM(DECODE(DTD_COURSE,'PASS',SCORED_FUTURE,0)) AS "PASS_FUTURE",
SUM(SCORED_TO_DATE) AS SCORED_TO_DATE
FROM QRY2
GROUP BY PAP_ERA, PAC_PCCT, WPE_JOB
ORDER BY PAP_ERA, PAC_PCCT, WPE_JOB;
Many thanks for your help.

P