[mothered]

the doorstep is highly unique owing to the structure of it, not statues or accessories. How do I go about selling the DNA?

Will the package be purely left at the doorstep and photos taken thereafter?

Yes, exactly that

In that case, photographic evidence Is useless.

They can take 100 photos of every angle, and It still won't change the fact that the package was left unattended, hence you didn't personally receive It.