Hello toiletmirror,
If I'm reading correctly:
You're going to install the sub-board you are holding into a vacuum chamber, and interface it
with DB15 connector?
If so, then there's nothing wrong with the idea.
You just have to ensure you ground the connector to the chamber with the original connector
ground.
It wouldn't hurt to use heat-shrink sleeving on each wire end to insure better insulation between
each pin.
Its also important that you pre-tin the ends of your wires prior to attaching them to each pin.
Regards,
Relayer