Can my old boss create a hostile work environment by bullying my current boss?

My current manager is an interim. My previous manager keeps coming back to our department and bullying my new manager and punishing employees and making them do tasks like clock back in a work more or comment on their clothing. They have gone as far as calling employees on their day off in front of everyone trying to get them to taddle on other employees. I told HR of this behavior but it kept happening for at least a month. Is this considered a hostile work environment? Also, the old manager keeps texting a certain employee to get information and calling and harassing employees trying to find problems that are happening. I told my current manager that I didn't believe that this was ok or right to do so they held a meeting with all managers and confronted them about this behavior. While in the meeting the old
Manager mentioned she didn't pick an employee to come and help her department because of her disability of not being able to walk up or down stairs. None of this feels right. Is this discrimination? The next day after the meeting I got a verbal warning for confronting my boss about a rumor I heard of him taking another employee to dinner. He said it was for a work event I said "ok" and sat down and started to work again. He claimed I was yelling, but the whole time I kept saying "you don't have to explain anything to me!". And him and the another employee kept at me until I said I'm going to HR......I need advice.