Originally Posted By: wagga
The photo (Tintype? Daguerreotype?) appears to have been taken after the Civil War, when there were conservatories to the sides of the White House, but before the East/West Wings were built.

Are we to assume that the event took place at or before this time?

Assume? No. Conclude? Maybe. If by this time you mean "After the Civil War, but before the wings were built".
Wherever you go, there you are.