I found this for 25 cents at a 50% off bin at the portland oregon show yesterday. It looks like it has a worn S to me, and even a VDB First pic is of date Second is the reverse where the vdb appears to be there but very worn
If there was a mint mark there, it would be raised like the remaining date? It is just circulation damage like the other areas of this coin is suffering.
I will give you a slightly different opinion. I have heard of/seen pictures of many weak VDB cents. I can actually believe that could be a 1909- VDB. However, what you are circling for your "S" is the wrong place and the wrong size. There is no way there is an "S" there.
If you hold your mouth just right and squint with one eye closed, you can make out what appears to be an "S" under the date in the last image provided, but alas, it is the wrong shape and in the wrong place. Post Mint Damage, circulation handling may have contributed to this pseudo-mark. Keep looking. Happy Collecting