Good day and welcome!
Seems that “Market Street Clock” already exists in the database at the same location as this (based on the Dr. Martens). Been seeing reports of “various rejection criteria” for duplicate rejections like yours.
You can check the submission map for wayspots not in PoGO when the blue toggle is on. It only works at a limited vicinity and may take time to load (not to mention bugged in some language settings).
Not all accepted wayspots are guaranteed to be used in all games, inclusion rules by each app team controls those. Here’s a guide for PoGO:
https://pokemongohub.net/post/article/comprehensive-guide-s2-cells-pokemon-go/
For future nominations, it is best to center the POI/object in the main photo for best results.