Can a new member ride as a passenger in a CAP Corporate aircraft if the new member has a CAP ID card (temp or permanent), but has NOT completed Level I and Cadet Protection training?

Yes, regulations do allow a new member with a CAP ID card to ride in CAP aircraft under the restrictions and conditions outlined in CAPR 70-1.  (Note: Your wing may have established a requirement for members to complete initial training before riding in corporate aircraft.)