The Bug
Mobs hurt by firework rockets fired from crossbows don't trigger player_hurt_entity or player_killed_entity advancement criteria.
In relation to MC-165262, although neither tamed wolves nor crossbow-fired firework rockets trigger the player_kill_entity criteria on their own, sometimes if you use both firework rockets AND wolves, it DOES trigger for some reason.
Thank you for your report!
We're actually already tracking this issue in MC-111473, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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