Sorry for the not so satisfactory update lol. So I didn't actually take out the wheel itself. I misspoke. I couldn't find a screw to tighten the casing down. But I could press on it and noticed the gap would close and the wheels wouldn't rattle back and forth. So I used a little bit of glue and glued the casing "shut" basically.
In hindsight, it might not have been the best way or correct way to go about it, but I liked the pickup and now I can play my j45 without the rattle from it.