SQL Server 2022

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DECLARE @T1_Customers TABLE (T1_Customer_id INT, T1_FName VARCHAR(50), T1_LName VARCHAR(50))
INSERT INTO @T1_Customers VALUES 
(1,'John','Darwin'),
(2,'Jane','Doe'),
(3,'Bobby','Black')

DECLARE @T2_Classes TABLE (T2_Class_id INT, T2_Customer_id INT, T2_ClassType_id INT, T2_ClassName VARCHAR(50), T2_Status VARCHAR(50))
INSERT INTO @T2_Classes VALUES 
(1,1,1,'Emergency Medical Dispatch v1','Pass'),
(2,1,2,'Emergency Medical Dispatch Instructor','Pass'),
(3,2,3,'Public Safety Telecommunicator','Pass'),
(4,2,1,'Emergency Medical Dispatch v1','Pass'),
(5,2,1,'Emergency Medical Dispatch v2','Fail')

DECLARE @T3_ClassTypes TABLE (T3_ClassType_id INT, T3_ClassType VARCHAR(50))
INSERT INTO @T3_ClassTypes VALUES 
(1,'EMD'),
(2,'EMD-I'),
(3,'PST')

SELECT * 
FROM @T1_Customers t1
LEFT JOIN (
  SELECT *
  FROM @T2_Classes t2 INNER JOIN @T3_ClassTypes t3
  ON t3.T3_ClassType_id = t2.T2_ClassType_id
  WHERE t2.T2_Status <> 'Fail' AND t3.T3_ClassType <> 'PST'
) t 
ON t.T2_Customer_id = t1.T1_Customer_id;

T1_Customer_id	T1_FName	T1_LName	T2_Class_id	T2_Customer_id	T2_ClassType_id	T2_ClassName	T2_Status	T3_ClassType_id	T3_ClassType
1	John	Darwin	1	1	1	Emergency Medical Dispatch v1	Pass	1	EMD
1	John	Darwin	2	1	2	Emergency Medical Dispatch Instructor	Pass	2	EMD-I
2	Jane	Doe	4	2	1	Emergency Medical Dispatch v1	Pass	1	EMD
3	Bobby	Black	null	null	null	null	null	null	null