Answer
Check the database's job_queue_processes parameter — query it with SELECT * FROM v$parameter WHERE NAME LIKE 'job%', and if it's showing as zero, that's why queued jobs (including IFS Connect tasks relying on the Oracle job queue) aren't actually being picked up for execution. Setting it to a non-zero value (e.g. ALTER SYSTEM SET job_queue_processes = 10, run by someone with DBA privileges) unblocks processing without needing to touch IFS Connect's own configuration at all.