All satellite sensors have ephemeral data which we use to create the photos with their initial approximations in object space. These parameters are stored in the the form of Rational Function Coefficients. One could then go straight to stereo display and feature collection but the fit wouldn't be very good. With ISDM-QB you can then enter MultiPhoto Orientations to measure control points, and then use Triangulation to compute a bundle adjustment and update the RFCs.
The customer would have to upgrade to 4.1 ISPM, ISDM, ISDM-QB