I think that this is the key statement of B, and one which wins him
the argument almost by chance due to his wording.

He states that there is one thing, but then qualifies this one thing:
"a clay statue of a ballerina". He is free to do so, because he is
making the statement, and thus imposing the "point of view" on the
situation.

If, in this situation, the one thing is equal to "a clay statue of a
ballerina", and not just "a ballerina", then I do not see how the clay
itself could be a separate, distinct object, since it is included in
B's definition of the "thing".

For example, if it were a pitcher of milk, instead of a clay statue of
a ballerina, then I do not think a similar argument could be made so
that there are both "a pitcher of milk" and "milk" on the table
without changing anything about their placement/orientation.