I am having the same problem It appears, when resolved from Unity and then sent to a Queue that it ALWAYS defaults to the DEFAULT QUEUE even when marked with another queue. You can see my code at:
http://hangfire.discourse.group/t/jobs-in-enqueue-state-most-never-run-sql-only/2367
After running it appears stuck in the default queue:
I do the same as @abdulbasit (Requeue via dashboard) and it runs:
This is driving me nuts! 