Entity Framework Core Inheritance TPT (Data sharing)

This question has already been asked here , I have another problem.

A person can be both a student and an employee in the same organization I made a TPT diagram I have two problems

• To add an employee who is already a student I must use raw SQL (or vice versa)
• If I do the employee reader I have to create a new DbContext to do the student reader. If not I will have a CASTE error

Entity code

[Index( nameof(FirstName), nameof(LastName), nameof(BirthDate) ,IsUnique = true)]
    public class Person
    {
        [Key]public int BusinessEntityId { get; set; }
        [Required] [StringLength(50)] public string FirstName { get; set; }
        [Required] [StringLength(50)] public string LastName { get; set; }        
        [Required] [DataType(DataType.Date)] public DateTime BirthDate { get; set; }        
        public Guid Rowguid { get; set; }
        [Column(TypeName = "datetime")] public DateTime ModifiedDate { get; set; }        
        [ForeignKey(nameof(BusinessEntityId))] [InverseProperty("Person")] public BusinessEntity BusinessEntity { get; set; }

        public override string ToString() => $"First Name : {FirstName} -- Last Name : {LastName}  -- Birth Date : {BirthDate}";
    }

    public class PersonConfiguration : IEntityTypeConfiguration<Person>
    {
        public void Configure(EntityTypeBuilder<Person> builder)
        {
            builder.HasIndex(x => x.Rowguid).IsUnique();

            builder.Property(p => p.Rowguid).HasDefaultValueSql("(newid())");
            builder.Property(x => x.ModifiedDate).HasDefaultValueSql("(getdate())");
        }
    }

public class Student : Person
{        
    public Guid RowguidStudent { get; set; }
    [Column(TypeName = "datetime")]  public DateTime ModifiedDateStudent { get; set; }
}
public class StudentConfiguration : IEntityTypeConfiguration<Student>
{
    public void Configure(EntityTypeBuilder<Student> builder)
    {
        builder.ToTable(nameof(Student).Pluralize());

        builder.HasIndex(x => x.RowguidStudent).IsUnique();
        builder.Property(p => p.RowguidStudent).HasDefaultValueSql("(newid())");

        builder.Property(x => x.ModifiedDateStudent).HasDefaultValueSql("(getdate())");
    }
}

public class Employee : Person
{ 
    public  Guid RowguidEmployee { get; set; }
    [Column(TypeName = "datetime")] public   DateTime ModifiedDateEmplyee { get; set; }
}

public class EmployeeConfiguration : IEntityTypeConfiguration<Employee>
{
    public void Configure(EntityTypeBuilder<Employee> builder)
    {
        builder.ToTable(nameof(Employee).Pluralize());

        builder.HasIndex(x => x.RowguidEmployee).IsUnique();
        builder.Property(p => p.RowguidEmployee).HasDefaultValueSql("(newid())");
        builder.Property(x => x.ModifiedDateEmplyee).HasDefaultValueSql("(getdate())");
    }
}

public class BusinessEntity
{
    public int BusinessEntityId { get; set; }
    public Guid Rowguid { get; set; }
    [Column(TypeName = "datetime")] public DateTime ModifiedDate { get; set; }
    [InverseProperty("BusinessEntity")] public virtual Person Person { get; set; }
}

public class BusinessEntityConfiguration : IEntityTypeConfiguration<BusinessEntity>
{
    public void Configure(EntityTypeBuilder<BusinessEntity> builder)
    {
        builder.HasIndex(x => x.Rowguid).IsUnique();
        builder.Property(p => p.Rowguid).HasDefaultValueSql("(newid())");
        
        builder.Property(x => x.ModifiedDate).HasDefaultValueSql("(getdate())");
    }
}

Code DBContext

    public DbSet<BusinessEntity> BusinessEntities { get; set; }
    public DbSet<Person> Persons { get; set; }
    public DbSet<Employee> Employees { get; set; }
    public DbSet<Student> Students { get; set; }
   

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);
        modelBuilder.ApplyConfigurationsFromAssembly(typeof(SchoolContext).Assembly);
    }

Add data

var businessEntity1 = new BusinessEntity() { };    
var studient = new Student() { BusinessEntity = businessEntity1, FirstName = "John", LastName = "Doe" , BirthDate = DateTime.Today };
    
dbContext.AddRange(businessEntity1, studient);   
dbContext.SaveChanges();
    
var id = dbContext.Persons.Select(i => i.BusinessEntityId).Single(e => e == businessEntity1.BusinessEntityId);

dbContext.Database.ExecuteSqlRaw($"EXEC ( 'INSERT INTO Employees (BusinessEntityId) VALUES ({1});')", id ); //Another solution to add an employee who is already a student

Data reader

Console.WriteLine("Students");
foreach (var p in context.Students)
{
    Console.WriteLine(p.ToString());
}


using var context1 = new SchoolContext(option); // I can't use the same context
Console.WriteLine("Employees");
foreach (var p in context1.Employees)
{
    Console.WriteLine(p.ToString());
}