Coworker is intimidating me by taking items from teammates’ desks and putting them on mine
Im a woman in my early 20s working at a tech company. The coworker in question was a friend (outside of work, coincidentally became close friends through a mutual), until I figured out that he was extremely manipulative and a creep. This all came to ahead when he suggested that I pull an April fools prank on my teammate that would basically involve ruining all of his measurement results. Up until then, he had been making little suggestions to try to get me to isolate myself from my team. He has also been egging on some of my more “wacky behavior” (I’m autistic/adhd and can sometimes be a bit much), likely to tarnish my reputation. Now I believe that he has been placing my coworkers belongings on my desk(s) to either get me to behave crazily, or ruin my relationship with my coworkers. This has happened twice (a mouse, and a pcb). I’m not sure if I want to bring this to hr yet, because it will just be my word against his at the moment, and my stocks vest in a month. I’m also worried about the confounding factor of us being friends previously, and still being in the same group chat (I’m afraid he’ll isolate me from my friends, so I haven’t told them or left the chat). So realistically, I don’t want to escalate this to HR until after my stocks vest, but I need someone at work to keep an eye on me and this situation. There is a security camera that may have captured at least one instance of him tampering with my desk (I know the date and time of this incident) but I don’t know if it is too far away or angled incorrectly. I don’t know the company’s retention policy, but I know that I need to act fast. If I bring these concerns to security and ask for them to find the footage, will they have to report the incident? How the hell do I deal with this situation in a way that won’t get me moved off my team? Also the company I work for has notoriously terrible HR.

Im a woman in my early 20s working at a tech company. The coworker in question was a friend (outside of work, coincidentally became close friends through a mutual), until I figured out that he was extremely manipulative and a creep. This all came to ahead when he suggested that I pull an April fools prank on my teammate that would basically involve ruining all of his measurement results. Up until then, he had been making little suggestions to try to get me to isolate myself from my team. He has also been egging on some of my more “wacky behavior” (I’m autistic/adhd and can sometimes be a bit much), likely to tarnish my reputation. Now I believe that he has been placing my coworkers belongings on my desk(s) to either get me to behave crazily, or ruin my relationship with my coworkers. This has happened twice (a mouse, and a pcb). I’m not sure if I want to bring this to hr yet, because it will just be my word against his at the moment, and my stocks vest in a month. I’m also worried about the confounding factor of us being friends previously, and still being in the same group chat (I’m afraid he’ll isolate me from my friends, so I haven’t told them or left the chat).
So realistically, I don’t want to escalate this to HR until after my stocks vest, but I need someone at work to keep an eye on me and this situation. There is a security camera that may have captured at least one instance of him tampering with my desk (I know the date and time of this incident) but I don’t know if it is too far away or angled incorrectly. I don’t know the company’s retention policy, but I know that I need to act fast.
If I bring these concerns to security and ask for them to find the footage, will they have to report the incident? How the hell do I deal with this situation in a way that won’t get me moved off my team? Also the company I work for has notoriously terrible HR.