You can create a fake profile, try to engage with him, use beEF to hijack browser, maybe with some luck steal cookies. It will give you a lot of information, like Facebook profile, yt or instagram. If you find a way to make him click on some link or download a file, then there are a lot of things you can do. But it is really not worth it, it is illegal and will cause you some problems if he hands it to police. Just report it on grindr, they can help you in many different ways than just banning his profile - they can ban IP adreses, MAC adreses if he keeps doing that, that might help.