Naming this organic compound
I think your teacher is correct, numbering of carbons is done acording to the lowest locant rule.

The red numbering gives you : 2, 3, 3
The green numbering gives you : 2, 2, 3
We see that the first point of difference between the two numberings occurs at second number, so the green numbering is preferred.
Consequently, the correct name should be : 3-Bromo-2,2-bis(4-chlorophenyl)butane