If that was my bike I would do the following:
1. Remove the bolt and pull the insert out of the tube,
2. Clean any daggy bits off both the insert and the tube,
3. Ensure the insert still has a relatively firm fit,
4. Clean both the tube and insert with brake cleaner or similar cleaner which doesn't leave any residue or dust. I would use MEK to clean the parts as I have access to it, the preparation areas and the PPE required to use it, but brake cleaner would suffice,
5. Mix up some 24hr Araldite, not the 5min stuff as the 24hr stuff is stronger and apply it to both the insert and the inside of the tube,
6. Re-assemble parts and wipe off excess Araldite,
7. Carefully reinstall rear wheel which is to ensure correct spacing and alignment of the dropout and stand bike as upright as possible,
8. Leave bike undisturbed for at least 24hrs but 48hrs would be preferable to ensure adequate curing time.
Hope this helps.
Cheers
