Section (7) gives an exemption to Sections (1) through (6) "where a statute specifically authorizes or directs an agency or person specified in subsection (1) of this section to regulate a subject specified in subsection (1) of this section".
I know of no statute that fulfills this requirement except KRS 237.115, which deals exclusively with concealed weapons. That was the purpose of Section (7), to allow cities to use 237.115.
This is a quote from a Ky. League of Cities advisory to all its members, "A city cannot prohibit citizens from openly carrying deadly weapons anywhere on city property."
You can see this advisory in full at:
The answer to your question is, no. Cities cannot regulate openly carried firearms in any manner and cannot prevent employees from openly carrying a firearm or discipline them for doing so. However, you must be smart about approaching them about this. They can always claim to fire you for some other, fictional violation. Members of this board have had that happen to them on several occasions. Let someone else handle this for you, someone that doesn't work for the city, someone they can't touch. If you send me some documentation of this I think I can do it. I'll need a copy of their official policy and/or pictures of any signs.