If this plaque is for this point of interest that is already a Wayspot, it would also be in the same L17 S2 cell and not be eligible to appear in Pokemon Go
I have this written up to try to explain to people looking for their pokestops:
I know the prompt tells you that you are submitting a “Pokestop” but you are actually submitting a Wayspot to Niantic’s Lightship database. The Wayspot can only become a Pokestop or gym if it is alone in a level 17 S2 cell. This is a good article about S2 cells and PoGo: https://pokemongohub.net/post/article/comprehensive-guide-s2-cells-pokemon-go/
I hope this helps. But I also caution people not to use this information to misplace a pin. That would be abuse.