Try this query:
SELECT T0.[TransId],T0.[U_BA_REF], T1.[U_BA_REF], T2.[U_NAME] as 'Updated User', T3.[U_NAME] as 'Created User', T0.[CreateDate], T0.[UpdateDate] FROM OJDT T0 left join AJDT T1 on T0.[TransId] = T1.[TransId] left join OUSR T2 on T2.userID = T0.usersign2 INNER JOIN OUSR T3 ON T1.userSign = T3.USERID WHERE T0.[TransId] = 'xxx'
Replace XXX with your transID.