my thoughts,
nobody has the right to defame anybody regardless of his/her status in life. considering your inquiries, if the building owner utter defamatory words that would cause public humiliation this incident would best be considered slanderous. Those employees like you that were present everytime the lessor of your employer act in a slanderous and defamatory manner, with the consent of your employer, you can escalate this issue before the office of the barangay in your area. This can be mediated upon by the Barangay Lupon, in the event that the building owner ignores your complaint on two (2) set hearings you can secure a copy of a certificate to file action from the barangay handling the case. This is a mandatory requirement whenever you intend to institute a criminal action against the building owner. A case of Oral Defamation and Slander by Deed can be instituted against the building owner. Do not be moved by the threat of being evicted in the building, I assumed that your office entered into contract with this building owner and the company you are working for is not in anyway a party to this issue.The contract of your office to the building owner is binding and the building owner can not just threaten to evict your company without just cause and due process of law. Whatever is stipulated in the contract shall be respected.