It seems I figured out my problem. It turned out that I'm a moron :-) While troubleshooting a dead fibre cable I inadvertently moved a cable from one HBA to another thereby invalidating one of the...
aha. Thanks for the detailed question.
Dual path for the two 2540's via two HBA's :D (SG-XPCIE2FC-QF4)
Single path for the one 6140 via one HBA :rolleyes: (SG-XPCIE2FC-QF4)