I don't know how those are held on.
They are metal knobs correct?
I meant pre 2013 bats on older ones like an older freak plus.
I had one break off completely and used epoxy to fill the hole where the rod goes, then used a screw to hold it together as any hard drops would break the epoxy resin over time. I fixed this a few times before I did the screw technique. After the screw into the epoxy, it never broke off again then the bat cracked so it was a permanent fix.