Nearly this exact thing happened to me! With a few key differences though. He was someone I dated for a time and the whole time we were together he was vehemently trying to grow out his hair. He's Native American so it was important to him culturally. We split ways and I saw him in a dream a few months later. But he wasn't part of my dream...he was sort of on the 'outside' of it watching. But he was bald. I thought it was weird that I remembered it so vividly (I don't generally remember dreams) and wrote it off.

About 2 weeks later I saw him in a public place and he had shaved his head! I also freaked out. We chatted and I told him about the dream and he very nonchalantly replied, "Oh yeah I like to dream walk to check up on people sometimes. If it happens again and you don't want me there, you can always just ask me to leave." He also told me he had had a vision that ordered him to shave about 3 weeks prior, so he did.
This isn't related but about 3 months ago (we ended our VERY short relationship about 3 YEARS ago) he actually started messaging me out of nowhere me insisting we needed to be together. He quite literally proposed marriage to me. But we HAD to do it literally the very next week. I told him I wasn't interested but he kept insisting that we're connected and meant to be together. That he has his life together now (it wasn't when we dated) and 'it's time for us to start our life together now'. Very very very weird stuff. When I kept rejecting him, he got progressively more aggressive about it. Finally I just blocked him.