var query = (

        //Customers

        from customer in context.Customers

​

        //Engineer 1

        join engineer1 in context.Employees on customer.PrimaryEngineer equals

        engineer1.EmployeeId into eng1 

        from engineer1 in eng1.DefaultIfEmpty()

​

        //Engineer Top

        join engineerTop in context.Employees on customer.TopEngineer equals 

        engineerTop.EmployeeId into top

        from engineerTop in top.DefaultIfEmpty()

        group new {customer, engineer1, engineerTop} by new {CustName = customer.Name, EmpId1 = engineer1.EmployeeId, EmpId2 = engineerTop.EmployeeId} into grp

        select new

        {

            Name = grp.Key.CustName,

            EmpId1 = grp.Key.EmpId1,

            EmpId2 = grp.Key.EmpId2

        });