Renegade-Traceur: After reading the log about the newly placed sign under the cache I renewed my efforts to get in contact with the property manager.
I finally succeeded and arranged a meeting at the cache.
He promptly brought me over to a property marker, which confirmed it was on public property.
Well informing him that he was reading the marker wrong didn't help as much as I thought it would and he became very upset/belligerent. He said something along the lines that he was going to tear it down whether or not it was on the company's property.
So I have decided to just remove it and accept that some people can't be reasoned with.
It is unfortunate being many people seamed to like it but if there is a person hell bent on not letting it be then there is nothing I can do.
Thank you all for all the fun,
Renegade~Traceur