Assuming there is only one HBA and no failover intended.
The card is an HP 468405-001 or 487738-001 with 6x Mini-SAS OUT and 2x IN internal. Its 1x external connector is dubbed 'HPE Tape.'
If I connected my HBA (which resides at a separate box) to this external connector, would it work with the drives connected to the 6x internal OUT connectors?
I suspect it should. A standalone LSI External SAS Switch box, for example, is by default port-agnostic.