Six months back, I used to work in a company which was a start up located in India. I left the company around April 2020 (during pandemic). Due to that I couldn't collect any certificates. After that, when the pandemic had died down, I gave a request to the CEO for experience certificate, relieving letter and pay slip. But the CEO didn't give pay slip, saying he will give it later. As I was unemployed at that time, I didn't follow up with him.
But after I left the company, I had a conversation with the new HR in that company in LinkedIn. During that conversation, I disclosed the faults of CEO and company. She being a sadist, conveyed what I told her in the conversation with her to the CEO. This infuriated my CEO and he said he will give a bad impression about me in my background review. After that, now I got an offer from a new company and they are asking for pay slip. I asked him for the same, but he has been delaying it for a week now giving me flimsy reasons like HR is not there or he is busy. The HR who had worked there has left the company. Even when I was working, usually HR's don't last more than 3 months and some of them come occasionally to the office. I don't even know whether there is a real HR there. How can I get the pay slip from CEO? If I file a complaint, what will happen if he gives a wrong background review about me? What is the ideal decision here, as I can't keep delaying the pay slip to new company (which I did convey to him).