What makes you think this is a SCSI connector? It might be... but it might be something else also...
I do not know the internals of the VM3100 - but I do know the VS1680, and have a full service manual for it
In the 1680 the IS a 50 pin SCSI connector unused internal, (although some units I have seen do not have the connector loaded, just the place for it on the board)..... but there is also an identical 50 connector that is used by factory test - and an identical 50 pin connector is the connection for the IDE hard drive.
The RBUS uses a 25 pin connector - I do not know why there would be a 34 pin connector involved.
If someone had a service manual for this we could sort it out.