I just realized I never fully addressed your problem! Sorry Chris!
You can swap the RA and Dec cables on the 900 mount. Depending on your cable harness setup, this might require some contortion on your behalf. If you switch the cables and the problem follows the Dec cable, it is either the cable or the CP2. If the problem stays on the Dec axis, the problem is mechanical in nature.
Email me directly when you have tried this, so we can work on it together.