The answers here explain that looking at revision history will show who offered bounties.
However what to do when no revision history is available? Like in this question, the first answer has been awarded a bounty but no revision history is available.
How to view the revision history or find out who offered bounty in such cases?
If bounty events are added to revision history, should there be a revision history even when the answer has not been edited even once since the beginning? Is that a bug?